I'd assume the bit about "Only Bad Endings" is directly tied to "Female Protagonist" tag. In other words, it's only bad in the sense that you are the female, and females generally don't care much for getting raped. Dunno. Kind of a weird combination, though. I'm always up for some rape and humiliation, but it doesn't seem that appealing unless I'm the one doing the raping and humiliating. To each their own.
That is what the Player is doing in this game,
I suppose "Female Protagonist" here refers to
"the pool of targets the Player is interested in is just one single female"
and "Only Bad Endings" means in this game:
the Player can -only- win
(as in it's morally bad to do the deed)
because he doesn't care about losing (about not going after the target)
so in typical Rapist MC game manner: the "Good Ending" (suddenly being visited by God and becoming a monk) is nonexistent