A "galge" is a genre of Japanese visual novels, typically featuring romantic elements with beautiful girl characters. Players make choices throughout the story, influencing its progression and leading to various endings. The game's outcome and which heroine's route is taken depend on the player's decisions.

by GPT-4

https://ja.wikipedia.org/wiki/%E3%82%AE%E3%83%A3%E3%83%AB%E3%82%B2%E3%83%BC