and here is the alternate ending version, where mc failed to save his girlfriend and his sister
SPOILER BELOW !!!
heroine is mindbroken almost beyond repair, and mc only aware after its too late only after mc saw the heroine got mindbroken then he confront the ntr guy
so this ending only happen because mc is clueless about the heroine situation and ntr guy is free to drug and mindbreak both heroine.
ntr guy propose to mc that he will save the heroine, only if mc accepting his proposal in return of ntr guy taking care the heroine, mc must become ntr guy henchmen, also forced to watched the ntr guy and heroine sex tape everyday
in short, ntr guy got the heroine, heroine is addicted to ntr guy dick (because of the proposal, ntr guy taking this chance to further train the heroine so she is addicted to his dick), later married and having daughter (page 35)
oh also, the one having sex with the daughter (page 36-63)is none other than mc himself ... hahaha what irony and its not out of love or anything, just the daughter is curious about sex, only thinking about mc as some kind of sex outlet. author explained that the daughter personality is really similar to ntr guy, while the appearance is the same as heroine
and lastly, about the mc sister author cant include the sister story in this cg because not enough time, still the author explained that mc sister is prostituting herself somewhere in this ending
so there it is, a nightmare for the mc, but at least in this ending mc got some action with the daughter