If you recall back when Kurono was heading to Spada, but was ambushed by the two Apostles along the way, I mentioned that there was one survivor besides Kurono's party with them, but never went into detail about it. The other survivor was a low ranking Adventurer named Simon (a very girlish looking Elf boy, who Lily almost straight up murdered because one time she noticed Kurono was missing, and the other adventurers told her that they saw him sneak away with a cute Elf girl, and that he was probably stressed out and pent up from leading everyone and so snuck away for some fun). Simon is actually using a rifle, which is what caught Kurono's attention. In this world however, even though basic firearms were invented, no one really uses them because they're pretty much ineffective against any decent rank monsters, there's spell casters around who can use magic that is much deadlier, and with superhuman strength taken into account, even bows can be deadlier with longer range and much faster fire rate. Simon's the adopted son of one of Spada's four most powerful noble families, and his older sister is the head of their household which helped a lot when they were crossing into Spada's borders because the Knights that ran into right away were under the command of Simon's sister. Simon actually more or less dropped out of his academy to go be and adventurer (from what I recall, he had his father's permission), and his rifle being weak was okay because he only hunted very weak monsters to earn just enough for a living so he could research alchemy. His sister is angry though because she thinks he should become a knight like everyone else in their household, despite Simon being very weak physically. When he returns to the academy though, the Dark Elf chairwoman Sofia (who is the head of another of Spada's major noble families) actually lets him right back in, and gives him a workshop too (most students don't get to have their own workshop), at the time it looked like she was doing it because of his family's position. Later on, Kurono basically sponsors him so that he can research without having to worry about money, and Lily also sneakily hires him as well, to recreate those "Angel Rings" that the crusaders were using to experiment with. Except her version is simplified, their version doesn't completely erase a person's personality, just suppresses most of it while keeping the important parts still active because they want their experimental soldiers to be able to think for themselves and be able to act without a crusader commander there with them. Lily just wants puppets though, so her rings doesn't have to worry about which parts of a person's mind are important and which aren't, the ring just needs to be able to completely erase their personality. Simon is scared, and knows that making something like that is definitely illegal, but can't help but feel excited at the prospect as a researcher and decides to make them for her.
The second important character that I need to introduce would be Wilhart, the second prince of Spada who is a chuuni. He also attends the same academy as Simon by the way. His older brother crown prince Aisenhart is known for being very strong and charismatic and will become the king in the future so he himself lets himself goof off. Aisenhart and the current king though realize that the two of them are kind of muscleheads, and that Wilhart inherited his mother's brain and is actually very smart even though he doesn't show it off. They also realize that Aisenhart becomes king he will probably end up relying on Wilhart for advice. The first time we see Wilhart is when he's dueling a single goblin in the forest while his maid/bodyguard Seria watches him, he basically just does some chuuni talk about this Goblin must be some legendary Goblin King or something, while he's getting his ass whooped and ends up only just barely being able to kill it. He ends up seeing Kurono rushing in and killing an entire horde of Goblins, and ends up nicknaming him "Nightmare Berserker" which ends up haunting Kurono to no end later. Later, when he's on a field expedition from the academy, his group is attacked and wiped out by a Wrath Pun, a rank 5 (highest) monster which is coincidentally a monster that Kurono needs to kill as one of the trials given to him by Demon King Mia Elroad. Kurono has Will and Seria run away because he doesn't think he can protect them and fight at the same time so they run away. Kurono's party cuts off its arm but it manages to escape though on the verge of death. It instead runs into Wing Road, a rank 4 adventurer party whose members include Charlotte (Wilhart's younger sister) who is a bit tsundere but worried about how a Rank 5 monster is near where her brother's expedition is camping out, as well as Kai and Safi (who are both from major noble families of Spada), and then the childhood friends of Wilhart and Charlotte, Princess Nell Elroad and Prince Nero Elroad (descendants of Demon King Mia Elroad, who was Emperor of the Elroad Empire, but started being called "Demon King" a long time later). The party's name Wing Road, is named after Nell who has a pair of white wings that she was born with. Nell actually ran into Kurono very shortly, nearby when he was having trouble getting his horse to move. Wing Road finishes off the Wrath Pun and gets all of the credit, and is promoted to Rank 5, with the record of the fastest party to ever reach Rank 5. Wilhart is angry about how they got all the credit, and makes a huge fuss for the next few weeks about how "Nightmare Berserker" was the one on cut off the Wrath Pun's arm and drove it off, and that's the only reason Wing Road was able to kill it so easily.
I can't remember how it gets brought up, but Kurono, Lily, and Fiona end up enrolling in the adventurer course at Spada's academy together. Lily remembers that the person who used to live in their house back in the forest had a lot of school romance novels, but for some reason it was always about two men.....
Kurono ends up running into Nell again in the academy's cafeteria, but Nell almost falls and Kurono catches her. Charlotte who sees this misunderstands it as Kurono harassing Nell since Nell gets hit on a lot; Charlotte attacks Kurono who fights back by restraining her with his dark magic, which ends up looking kind of like black tentacles. Nero who sees this gets angry and jumps in too, Nell stops him, and Kurono decides to leave to de-escalate the situation because he noticed Fiona and Lily were about to jump into the fight as well. As a result though, Kurono's reputation at the academy is pretty much ruined. Nell feels really awful about it, and wants to make it up to him, but doesn't know how. Around this time is when Lily and Fiona pair up to go look for human sacrifices to test out Lily's modified Angel Ring, afterwards Fiona sacrifices them to the Dark Gods of Pandora to try and get a Divine Protection. During this time Kurono is lonely because other than those two, his only friends are Simon and Wilhart, since everyone else at the academy stays away from him. During this time Simon and Wilhart also leave for an academy expedition. Nell finds him having trouble with magic, and offers to tutor him. They become friends during this time, and Nell offers to make lunch for Kurono during one of their tutoring sessions, and Kurono is excited to eat something made by such a beautiful girl. It turns out to taste awful though, and Kurono surprisingly enough actually tells Nell exactly that. It turns out that everytime she makes something, everyone tells her it tastes good no matter what, so this whole time she thought she was really good at cooking, and is embarrassed that she so proudly cooked for everyone when she was feeding them something awful. She's also happy though that she finally has a friend who is willing to tell her when she does something wrong. Kurono decides to enter the "Cursed Carnival" a death arena type event where winners can get a lot of money and cursed weapons as prizes, but is in danger of death while an audience watches. And even if they defeat their opponents, they might get possessed by the cursed weapons anyways. Nell who is worried about how dangerous it is, offers to be his healer. On the day of the event however, she comes across a brother and sister who are lost and scared; and they reminded her of herself and her brother, and how Nero would always sneak out to play, while taking her with him. She stops to help them find their parents, before heading to the arena, but is late to Kurono's match because of it. And when she gets there, Kurono's match is already almost over and she's only in time for the very last few moments of it. Kurono uses the spell that Nell helped teach him, and realizes that it made her happier than helping the two kids did. Kurono cuts off the head of his last opponent, but his hit by a counterattack from his cursed eyes at the last second and has his arm turned into crystal. Nell blames herself for the injury, thinking that she should have tried harder to discourage Kurono from participating, that she should have rushed here instead of getting distracted. Nell uses one of her kingdom's national treasures, a winged staff, to heal Kurono's arm. However, the staff has a limited number of uses, since instead of being a normal staff that works by boosting the spell caster's ability to use magic, it uses up special crystals in order to cast an extremely powerful healing spell, and the method to creating those crystals is unknown. Nell pretends to be tired from healing so that Kurono will carry her, he does in a princess carry which he jokes to himself about (he's carrying a princess in a princess carry position, then thinks that it probably would have been easier if he had just carried her on his back instead of trying to act cool). He gets a message from Seria (Wilhart's maid) with a letter from Wilhart about how they were ambushed during their excursion by a Rank 5 monster Greed Gore, and are currently holed up inside Iskia Fortress, an old fortress that was nearby. Because of their proximity, Nell is able to feel Kurono's emotions and also get glimpses of his memories, mostly of the burning village and all the people dead on the way to Spada. Then she sees when Kurono meets Demon King Mia Elroad, and realizes that this is when the Kurono she knows is born, when Mia Elroad tells him "You saved me". As an aside, the author constantly trolls about Mia Elroad's gender. The author likes pointing out that Mia Elroad likes to wear a male school uniform, but then also likes to point out Mia Elroad looks extremely feminine. And that although all official records state that Mia Elroad was male, tons of important people also believe that he was secretly female. Mia Elroad in the memory then points out that his/her descendants are quite rude to look at peek at someone else's memories, then erases Nell's memory of that specific memory. After that, Nell believes that Kurono will get into danger no matter what, so instead she should be by his side to make sure she can heal him next time, and even decides that she'll quit Wing Road. She thinks that since the other two members of Kurono's party left alone by himself, they must not care about him. As the two of them head out of the city they're spotted by Lily and Fiona who had just returned to Spada, and then Lily and Fiona chase after them while saying that they really were gone too long, since there's now someone clinging to Kurono.
After the battle with Greed Gore, Lily and Fiona finally catch back up to Kurono and Nell overhears how happy Kurono is to see them, and Lily giving her an evil smile.
It's unknown exactly when it happened, but academy chairwoman Sofia fell in love with Simon some time prior to the beginning of the story and helped convince Simon to try and become more independent from his family (to get him away from his sister). Also several years prior to the story, Sofia who was dying wandered into the fairy forest and had her life saved by Lily. Both of them remember this, and so have been getting along since Lily moved to Spada. Sofia is upset that she wasn't able to rush to Simon's rescue when she found out he was in danger, but Lily points out that it's not a problem (Kurono would have made it there first even if she did rush out), and Simon doesn't mind it either. What's more important is what she does from now on. Sofia decides that she doesn't care about what everyone else thinks anymore, if anyone gets in her way she'll just crush them. Lily mentions that she needs to buy a new bed, since a "winged insect" got on her old one.
Jumping back to the end of the previous post, a big part of the reason that it was okay for Kurono to keep the enemy supreme command around free, was because Wilhart stood up for Kurono and pointed out his contributions in the war, as well as the story about how Spada was formed (the first king of Spada captured a female enemy general and basically forced her into becoming his wife), so there was precedence for using enemy generals as slaves, he also pointed out that she had lost her Divine Protection of the White God, and actually gained a Divine Protection from one of Pandora's Gods. Though in the process of going to a temple and proving that, the temple actually starts to realize that Kurono has Demon King Mia Elroad's Divine Protection (the first person to ever have it). After Lily defeated the team of Nell + Sariel + Fiona, Fiona had a secret message sent to Kurono of a recording of their battle with Lily to help him plan. Kurono also receives another trial from Mia Elroad, previously he had been given trials to collect body parts of certain Rank 5 monsters, but this time the trial needed Lily's heart. He gathers up a team of himself, Kai (from Wing Road), Rudra (a very strong vampire who's obsessed with fighting), a famous gladiator of Spada, Simon, and a (secretly female) knight who is a childhood friend of Nell's. They use a formation with Kurono in the center that is basically using Kurono as a hostage so that Lily can't use her Heavenly Battleship to bombard them, because it'll hit Kurono too. Lily instead hits him with a stasis beam to freeze him in time, and then goes with fighting the entire rest of the party. Basically, the Kurono that was frozen was an empty suit of armor that he was transmitting his voice through, and after everyone else is defeated he challenges Lily by himself, after he freed Fiona, Sariel, and Nell. When he faces Lily the first thing he does is rip out one of his eyeballs, the one he received from Mia Elroad. He talks about how getting another divine protection wouldn't be worth losing Lily, and in fact that he doesn't care even if he lost all the divine protections he had collected up to this point (across ~600 chapters), he would just have to find another way to get strength. As soon as she saws Kurono injure himself Lily immediately stops fighting and rushes over to help him, but Kurono stops her. Kurono just barely manages to win, thanks to Simon hitting him with a dose of healing at the last minute, Lily asks Kurono if he loves her, and he says yes. Then she asks him if he'll marry her, and he says yes again. Then she rips out her own heart and gives it to Kurono so that he can offer it to Mia Elroad. Before he can do anything, the heart is absorbed out of the air. Kurono then rips out his own heart, and he manages to stay alive long enough to transplant it with magic into Lily's chest, he then shoves a monster heart into his own chest, and points out that he has no idea if this will even work, has it fused into his body. He wakes up on Lily's lap and is happy that both of them survived, however since Lily has lost her "Envy" she can't stay in her adult form 24/7 anymore, and so she reverts back to her child form. When Lily meets the Fairy Queen again, she thinks the Fairy Queen will be angry that she failed, and may even take away her Divine Protection, but is surprised when she's not angry at all, and reminds Lily of a mother, who is happy for their child no matter what. She says that Lily chose a different path of love than her, but that's fine too as long as she's happy.
When Kurono meets with Mia Elroad again, he's angry about the trial, but Mia Elroad reveals that the heart transplant method was a known loophole, though fully killing Lily would also technically count as a "success". Mia then warns Kurono about the White God. Back when Mia Elroad was human, he/she killed all twelve Apostles by himself/herself, but that was the limit of a human being. So even though Mia Elroad forced the White God and his believers completely off the continent, it's still possible for them to take it back. Right now the Apostles are careful about fighting on Pandora because their Divine Protection is weakened there, but if the White God's domain expands to Pandora (through belief), they'll become stronger. After Kurono leaves, Fairy Queen Iris arrives, and Mia Elroad blames the timing of the trial on her. Normally Kurono and Lily would have been given time to make their decisions, but Iris realized Lily was emotionally vulnerable and gave her a push.
Later, Lily and Sariel tell Fiona that from now on, they'll be sharing Kurono. Fiona doesn't want to agree, since up til this point she's pretty much had Kurono all to herself, but Lily and Sariel have teamed up and Fiona knows she can't win (both in strength, as well as in Kurono's heart since right now Kurono basically loves all three of them equally, even if he's still awkward with Sariel, so they have 2/3 of his heart, and she has 1/3). Lily even points out that there'll be more girls joining them from now on, since she wants to give Kurono everything. She is also purposefully keeping her relationship with Kurono as "Fiancee" instead of "Wife" because she knows that if they get married, he'll throw away Spada in order to prioritize her safety, but will regret it for the rest of his life.
When Kurono returns to Spada, Wilhart asks how Kurono would feel about marrying his sister (Charlotte), because due to his performance in the battle with Sariel, the country of Spada will definitely make moves to tie him to Spada, so that he will have a vested interest in protecting it, instead of being a free adventurer who can just leave Spada whenever he feels like it. Kurono almost has an aneurysm, he just finally finished up the business with Lily and Wilhart is immediately trying to throw in another girl into the mix (one who absolutely hates his guts too). However when the decision finally comes out, it's for Charlotte to marry Kurono, and Wilhart to marry Nell; previously Charlotte and Nero were planned to be married since they were childhood friends and got along very well. Wilhart is now worried that Nell is going to "accidentally" murder him if things go on as they are, so he contacts Nell and tells her that he has a plan to let her marry Kurono but she has to convince Kurono to go along with it. Which is also admittedly easier now, since even though she can't get Kurono all to herself now that the polygamy path has opened up, it also means it's way easier to get her foot in the door since she doesn't have to defeat Lily anymore.