Seduced by Bell-senpai!

He's already got his hands full keeping his half-succubus girlfriend Hinata's powers in check with regular makeout sessions, so naturally he decides the smart move is asking her senior Bell, a full-blooded succubus, for advice. Bell agrees to help, then immediately redefines "help" as pressing her enormous breasts against him under the label of practice.

The setup is simple: loyalty versus temptation, with Bell fully aware of which one she's rooting for. The protagonist spends the game insisting he won't cheat on Hinata while Bell's idea of tutoring gets less educational by the scene. Multiple endings are the only mechanic that matters here, since how far he lets Bell push things decides where his relationship with Hinata actually lands. It's a short, focused story built entirely around that one decision repeated in different shapes.