SPOILERS
Hidamari: the guy is the MC's bully and he pressures the MC to play it like they are friens in front of the girl when he encounters them in town. He manages to get the girl's number by pretending to care about the MC's recovery and offering to help his studies by passing along tests and other things from school, which goes fine until the MC finds out she has been meeting the antagonist to get those things and fess up to him being a bully. She decides to confront him at his house, he gets flustered but then makes up a story about how he initially just wanted to become MC's friend but got cut out, and then things escalated to the point he couldnt take back but he regrets everything and abandoned his ways and old buddies when the MC droped out of school because of what he did. Also, he says he has fallen for her and he wants to show her he's a changed man. Then, he put his buddies to harass the girl close to his house and chased them away in a saviour act. Roleplaying as taking revenge on him, the same buddies kidnap her and were about to rape her when he comes to save the day again. That's when he takes her to his house and uses her vulnerability to get her into bed the first time and convinces her they should go out since he loves her that much. The rest is pretty much gradually getting her to open up to him sexually and accepting the uncommon plays (no condom sex, cumming inside, toys, etc).
Honto: The guy was the MC's senior at high school (they werent acquainted) and works at the same place as the MC and the girl, while the MC and the girl get along and start going out, he tells her the MC had a playboy reputation at school and had awful rumors going around. She doesnt put up with it and they make a bet, that if he proves it to her then she has to go out with him for a day. He then calls the MC saying they need to meet at a bar for a serious talk, gets one of his girls to show up instead and she lures him into a cab just to drop him off later in the middle of nowhere w/o cell reception. The guy had guided the heroine to spy on the MC and see the whole thing. She gets distraught after the MC goes into the cab and doesnt answer his phone and is promptly required to pay the bet. He takes her to a friend's bar where they can drink unsupervised, then he takes her wasted to a hotel. She doesnt want to do anything but he convinces her the bet had certain implications and she has to, due to the chain of events she is not in a condition to argue and goes with it. The day after, she confronts the MC and everything is cleared up, she finds out it was all a set up but the antagonist plays it like he told her only half truths and she filled in the blanks by herself. Then, he promises not to tell the MC anything if she agrees to have sex with him until summer is over. From then on he uses a lot of tricks to get her to fall. He says he'll let her go out with the MC or reduce their time by weeks if she agrees to certain acts, and later he uses their time limit to bet if she can withstand certain situations, if so it is reduced, if not is is increased. By the time she is released from their contract she cant stand it and goes back to having sex with the guy behind the MC's back until he finds out.
