so, things go like this: MC Naoya, Wife Kanae, Father Nobuyuki, Kohai Ayumi and Daughter Rui
MC and his wife Kanae move to MC's father house after MC's mother died. MC and wife fucks and Father see everything. The father gets drunk and try to fuck kanae, she refuses but Nobuyuki is too insistent. Then the father proceeds to take his son's wife slowly by forcing her to do handjobs and sumata.
Meanwhile, when MC is working he get a kohai named ayumi. They get close but Naoya loves so much his wife he cant ever think about cheating
Days passed and Naoya most of the time is overworking so his wife is getting lonely and Nobuyuki meets Ayumi and blackmail her so he can to create the fake betraying plot of his son and show it for MC's wife . This is the first breaking point, if naoya accepts ayumi's offers the plan proceedes. then nobuyuki gets the perfect excuse for advanced with kanae(and fuck). After this Rui is born and naoya thinks is his daughter.
The second breaking point is when Naoya accepts Ayumi's offers ending in her aparment and he gets a blowjob.
* End 1: Naoya never accepts Ayumi's offers so the plan never proceeds. He and his wife never cheated each other and eventually leave the father house, two years after that kanae is pregnant with Naoya's child (happy ending, kinda)
* End 2: After blowjob and fuck with Ayumi, Naoya decide overworking again. He missed the festival for working but Nobuyuki takes Kanae to the festival (and they have sex and this is not the first time this happens) Naoya never discovers that her father and wife fuck when hes not in the house
Naoya decide not overworking and catch his father and wife fucking. They explain all its happend to this points. Naoya blame his father and gets two option.Threesome or divorce
* End 3: Naoya chooses a trio. Naoya can't get erect, so Nobuyuki fucks Kanae. After that Naoya, all this time is still not erect so nobuyuki is the only one who fucks kanae and naoya only can see.
* End 4: he chooses divorce. The family goes to visits MC's mother's grave and then to the beach, Naoya now see how his father and exwife fucks on the beach and in the house everytime when his take care of Rui
* End 5: Naoya blame his wife instead of his father. she talks about everything and naoya discovers all was set by his father. Naoya and Kanae get angry against Nobuyuki for everything he has done. The problem about the father is solved, MC's forgives his wife and they have a second child but Naoya nevers has the courage to try an ADN test about Rui and Kanae doesn't talk about it either.
Naoya gets the blowjob but stops before he fucks with ayumi. Time passed and MC and his wife's relationship is cold as ice. Time passed again and now the 4 characters are on the beach
* End 6: Naoya and ayumi fuck on the beach but nothing really happend. eventually MC discovers about his father and wife cheatings after cancel a date with ayumi. Kanae dosent love naoya anymore, too much time passed without affection, and they divorce
* End 7: Naoya never fucks ayumi in the entire story. Naoya finally has brain and see the strange behavior of his wife and discovers about the cheating. Angry and Sad, Naoya now proceeds to spy on his wife's activities and gather enough data to divorce
* End 8: In the same line as end 7 but naoya decides that he has already collected enough evidence. He divorces his wife and takes custody of Rui. Time passes and he discovers Rui is not his daughter but his half sister and with each year Rui looks more and more like Kanae. Eventually, they reach a point where they start an incestuous relationship because of that fact
