About my childhood friend who turned into a bitch ~ Me, Marin, and my sex friend

■Story

The main character, Hisashi Ono, has been with Marin Sakurai since he was a child.

 She still has a childhood friend who she often plays games with.

 Sometimes we get teased about our relationship, but it’s just a rotten relationship,

 She thought it wouldn’t be strange if Marin had a boyfriend, and she didn’t feel anything special about him, since she has a wide circle of friends.

 One day, after playing a game and chatting with Marin, she looked at the screen a while later and noticed that she had forgotten to turn off the camera.

 There, she saw her childhood friend letting a strange man into her room and having a titty fuck.

 Later, he finds out that he was watching, but he doesn’t really care.

 She also says that the other man, Eiki Shitaga, is not her boyfriend, but a sex friend.

 She was surprised that Marin was having sex with other people.

 Hisashi is shocked to learn that she has a sex friend and is having sex with multiple other men.

 He tells her to stop doing that, but she says that he just wants to have sex, so she gives him a blowjob.

 Moreover, her virginity was taken away from her without being able to resist.

 From then on, Hisashi becomes conscious of Marin and has mixed feelings about her having fun with other men.

 He once again tries to stop him from having sex with an unspecified number of people, but

 He points out that it’s because he just wants to monopolize her body, and he tells her that if he wants to have sex, he should become her sex friend.

 But he stubbornly refuses, saying that’s not what our relationship is about.

 After that, Hisashi continues to worry about his relationship with Marin, but

 In the meantime, as if to provoke him, she continues to show off her lewd behavior with her sex friend…