I've attempted to summarize as much as possible. Some of the dialogue follows a different flow but the content is basically the same. Some sections have more detail than others. My energy just kinda went up and down while writing this. Hopefully it's decent.
Brief:
Yoshino and her cousin start the mange off by discussing Kirishma's feelings towards Yoshino. Yoshino's cousin mentions that Kirishma went to see her when he was 12 years old but Yoshino doesn't recall meeting him. They wonder if he feels love or obsession. Yoshino believes it's obsession and believes that he'll stop being in "love" with her if she loves him back. That Kirishima prefers her rejection and hatred. Her cousin thinks he's in love. Her cousin also mentions that if he is obsessed then he'll be a problem when Yoshino leaves him and returns to Osaka. Then her cousin suggests that Yoshino may seem like an old ex-girlfriend of his. Yoshino can't confirm nor deny since she only talks about subjects like the food and news with Kirishima. Her cousin says that they've moved on from the honeymoon phase to the marriage phase.
At school: Yoshino is still wondering whether he's obsessed or in love. Then sees him in the hallway. The girls runaway and act very formally towards her. She's a bit put-off by their formality. Then she asks him what they were talking about. He was giving them information regarding school administration for registration. Apparently it was an assignment from the Moral Committee that he's a member of. Yoshino is surprised to hear it since he has no morals. He responds that he doesn't follow the law but he follows school rules and she calls bullshit.
At the staircase she says that she thought he was being confessed to. But Kirishima doesn't receive love confessions any more since he rejects all of the girls at school. Yoshino tells him that he's the type of guy that doesn't have male friends. He would piss them off too much.
Then he tells her that it's enough that he met her. She asks if she's like a guy friend for him. Possibly, he says, she's the first friend he's ever had in his life. It surprises the shit out of her since they only talk about food and the new. He mentions that she's the only one he talks to about those things.
The women he gets with just usually talk at him. He likes listening to them but he can only talk to Yoshino about those mundane subjects. She retorts that he's asked his first friend to marry him. He just tells her - yea, it's true.
Her thoughts fall apart after his statement. If this is true then he's not obsessed nor in love with her. He's just confused his emotions and doesn't even think of her romantically. Her discussion with her cousin (Tsubaki (finally got the name will use it from now on)) about his ex-girlfriends and worrying about his feelings were pointless. She questions the fact that she's been on her guard all this time. She feels like her efforts were all in vain.
At the club they're talking about a new character named Shiota Nao. She's a famous-ish actress at the club meeting with frenemies/colleagues (other models & actresses). They talk about networking for a bit. Then one of the girls sees an ex-boyfriend of hers. They ask when and why they broke up. She mentions that it was last year before she won a beauty contest. Her ex-boyfriend found out about the beauty contest and ask her why she was reaching for so much. She broke up with him over the statement.
The girls go quiet and then give lip service, like "you made the right decision." Her internal dialog reflects on the fact that the women she's with talk about her behind her back. They say she got acting work through the use of connections like her father. Also, that her personality would change with the people she's with. Which she agrees with but doesn't given a fuck because they're not that close. She doesn't see what's wrong with being two-faced.
Nao works harder than the others (she's probably referring to her beauty and "nice" attitudes towards people) so that she'll be liked. This type of lifestyle has other people favoring her and doing things for her without even asking. She doesn't sell herself cheap. She won't be the type of woman that will be loved only while she's young. She's studied and worked hard for that. Nao states (in her mind) that she's the most successful of their group.
In the conversation she gives an excuse that her ex worked a lot. That there were a few things that were breaking up their relationship. A frenemy worries that she's too clumsy and will fall in love with a "dangerous man." Nao denies it but another girl concurs.
Their conversation shifts towards Kirishima. A few of the girls know who he is, others are curious but Nao recognizes him. They mention that he's nice but there's a lot of weird rumors about him. They talk about the Gravure model he was sex friends with. Apparently she was an actress at first in a company with one of the girls. Then she became a gravure model and eventually switch to porn star before leaving the entertainment scene all together. The girl mentions that the porn star girl saw Kirishima start to go out with her friend. Then she says that shit happens. Another rumor pops up about Kirishima having a fling with the wife of the club's owner. (The club they're all at)
Nao remembers meeting him and having sex with him. She was overseas and came back for a bit then left again. It was during that time that they met and started up.
While she's remembering Kirishima comes up to them to greet the girl(s) but he and Nao act like they don't know each other. They're introduced and an upcoming event for Nao in Osaka is mentioned. One of the girls says he should go see her when it happens. He says I see and maybe, if he has time to.
She's surprised to have seen him and mentions that he's 18 or 19 and that she was in her first year in university when they first met. Their affair ended 3 years ago when he was fifteen (so she was 18 or 19 back then). She notes that none of the other women know about their affair. Apparently it was pretty steamy, they did it daily. She says that it was in response to her repressing herself all the time.
He pretended he didn't know her which was convenient for her. She messed around with him despite knowing that he was a dangerous guy. Now she'll pretend that she doesn't know him and avoid him. He shows up they talk about their fake first meeting and apologize to each other. He implies that she should pretend not to know him. He talks about the fact that it's been three years. He doesn't recognize her at first and that she act more Japanese. Before she'd just say things more directly. She basically says that she's adapting to her environment.
He tells her it's ok to be vocal. He gives her his contact info.
Back to Yoshino, she's trying to pick a good time for them to visit her family in Osaka. It's hard because they're busy due to school exams. There are also upcoming festivals which will make traveling more time consuming. Yoshino thinks that she'll visit the cemetery for just during the Bon festival even if they plan their visitation for another time.
Then she sees that Kirishima comes home and calls him to talk about the visit. That they'll need to go around the beginning of August. He asks if they can go during July.
He's looking at a post from Nao saying that she'll been doing a cosmetic's even in Osaka on July 31st. He tells Yoshino that he can't wait for Osaka.