This is a Spring Thing choice based game from a while back. It's a choice-based story about your friend and your stepbrother (a trans man) who get romantically involved while in high school.
This relationship is not a good one. The boyfriend becomes increasingly possessive as your stepbrother draws away from society. Things get physically bad.
The writing is expressive and descriptive but has some typos scattered throughout it. There are enough options that it feels like you have some real agency in the game but that is of course balanced by the fact that you can't always make someone make the right choice in a relationship. Interesting read. Contains some strong profanity.