VOL 2:
-new girl appears, her objective is to give ryuzaki the suffering he deserves.
- she seduces him and undermines the crushes the other girls had on him, the plan is once he had no girl to bounce back to, she would dump him and humiliate him.
-she tries to give MC back his whole harem plus shiho cause it would be fun mostly, MC thwarted her plans by having a face of with gyuaru/former library friend where he pretend to be a villain until she slaps him.
-shiho then faces new girl and says Mc is only hers (she would only allow Azusa because she is actually MC's sister but no one else, this was the first yandere-ish episode she had so far during the novel)
-in the end new girl gets defeated becuase from this supernatural charm, in the end she couldn't dump ryuzaki, she had fallen for him too.
-volume ends with gyaru girl getting part of her old identity back and moving on, even watching Mc and Shiho together and thinking she could have been there too if she wasn't so stupid before.
VOL 3:
-we get to know why MC is so passive, basically his mother's fault, we also get a lot of fluff with shiho's parents, sometimes they all feel like a big family with shiho and both nakayama siblings.
-ryuzaki loses his Mojo almost completely, then we understand how much his "protagonist" luck is based on his self confidence, we see a lot of his "outer harem" that includes like a dozen girls from upper classes and even the school nurse, fall out of love with him like flicking a switch, like it was an actual spell.
-the drama starts with an arranged marriage between the childhood friend and MC apparently it was settled years ago, but since both MC and the childhood friend have such passive personalities, she looks resigned to it, Mc decides he need to give ryuzaki back his confidence to make him go fight for her
-stuff happens, ryuzaki appears to try and break the engagement finally confessing to Yuzuki (mc's childhood friend) and... Gets rejected, but at least she also React enough to also reject the marriage.
-both gyaru and childhood friend meet with ryuzaki and decide to confess that they both still love him, now with more honest feeling, he decides to actually acknowledge them and asks for time to make a choice.
VOL 4: (light novel version, web novel version sucks)
-new girl appears, she was another childhood friend of MC but he thought she was a boy.
-she becomes a somewhat contender for the love of MC she is more direct and they begin spending more time together becuase of reasons. (note - until this point shiho and MC aren't a real couple yet, and you could say they've stagnated since he dotes too much on her almost like she was another little sister like Azusa)
-we get many flashbacks that basically reveal that new girl's grandpa is also shiho's grandpa, they're cousins, also Mc's mom had worked for grandpa or had some previous link, that's how they actually knew each other first than anyone else (remember the photo of both of them as babies in the Manga, that's the reference) so it was destiny.
-even after some botched confessions, there's no drama, triangle or NTR, not really, they just gain a cousin and good friend with new girl, ironically MC has three girls around him again, only different ones except for the sister who is the only one remaining from before.
-this volume also has a lot of slice of life sidechapters like onsen, sleepovers, etc.
VOL 5:
- it's basically a long epilogue, slice of life fluff, shiho ad MC finally become a couple for real and they go directly to engagement.
-there's a beach trip for MC and the three girls, it's supposed to be private but somehow there's a lot of people
-the crazy girl from second volume who now is a maid (don't ask) was the one trying to stir back some drama on the story, like triggering usual romantic comedy events to spice up things, even bringing ryuzaki and the other two former friends to maybe stir old feelings between everyone involved
-in the end MC and most of everyone else decide to leave the romantic comedy behind and simply go live a boring nice life, crazy girl cries and goes away, shiho and ryuzaki get their first honest talk ever, on the way home they stop to see the sky and then we get the 10 year timeskip to the wedding.
-Most characters attend, including Mc's distant parents and a cool young aunt he has, even ryuzaki and his two girls attend, actually right until the end it never gets confirmed if he ever picks one or even is in a relationship with any of them or both.
STUFF FROM THE WEB NOVEL:
-stuff that got changed for the light novel it was mostly for the better, to name an example, in the beginning Mc was constantly moping about the girls that left him, in the LN he's more detached... It is what it is.
-read the specials like Christmas or Halloween chapters, also there's a couple AU short stories like what if Mc and Shiho never met in high school that are nice, the best ones are the 19 years later chapters that come days or weeks before the wedding, those are amazing, specially one called "the last siblings fight"
-the WN is also dropping from time to time a few chapters about shiho and MCs life in college together
RELATIONSHIPS IN THE END:
MC obviously got his sister back, there are a lot of very cute moments between them during the story, I think they're better written tmeven than shiho and MC sometimes, with gyaru girl they become friends again but not close like before, shiho is scared of her for some reason, with the last girl, Mc and her basically come to the conclusion that they don't really like each other anymore.
Azusa moves on from ryuzaki, their was a small moment where she could have relapsed but she handled everything like a boss, new pink haired girl solved her brief crush with MC and simply stayed in a supporting role
MC and ryuzaki became constant "frenemies" sometimes even going to punches (at least once) and even having an honestly funny moment when he finally found out that all his girls had been MCs "hand me downs" (his words since he was in a very self loathing mood) but the guy actually had a lot of character growth even if he still was a jerk.