This is not a perfect, buty way above average metroidvania style platformer with an awesome soundtrack (available on Bandcamp)
It has some similar mechanics like other character change platformers (Gian Sisters Twisted Dreams), where the environment - and in this case NPCs - react differently depending on the chosen character. In this case the char changes gender, which can adffect platforms or doors (only boys can enter the mens restroom) or if NPCs will talk to the player or not.
It's a crying shame this didn't get a DRM free release yet.