I actually tried to make a game similar to this concept a really long time ago but just never went through with it. This was my idea: the game was called Love Story at the End of the World and the premise was it was a few nights before prom night at the MC's high school and they were beyond ecstatic. They were a hopeless romantic that wanted to fall in love and have the best prom night ever. However, a zombie outbreak occurred, causing everyone to be sent to bunkers. It turns out that the MC gets stuck in the same bunker with four of their classmates that they had been crushing on for years. They won't let an apocalypse stop them from having a fairytale ending with the love of their life so the game involves them pursing characters romantically and getting different endings based on their choices. The good ending would then be them dancing with their crush as if it was a normal prom night

I hope you find this helpful and sorry if it's all over the place. I wish you good luck on your game :)