Let’s Steal Away My Beloved Nurse Sister

MC grew up in a hospital, raised almost entirely by his attending nurse Mina-oneechan, and the childhood promise to marry her never quite left him. Puberty turns that promise into something uglier when he finds out she's engaged to his own doctor.

That discovery is the whole engine of the story: a kid who idolized the woman who raised him now has to watch her belong to someone else, and decides he isn't going to let that stand. What follows is less romance than obsession, jealousy curdling into manipulation as he looks for ways to pull her away from her fiancé.

You move through the hospital making choices at key story branches, watching the relationship between Mina and her fiancé sour as MC's influence over her grows. The game tracks toward multiple endings depending on how far you push things. One practical note carried over from the source: turn off Always Dash after the fourth choice, or a popup message won't stop nagging you.