this one is twine but i give it a 9/10 so far and its still being developed so new stuff will come [
Insatiable Hearts [v0.1.3C] - A monsterfucker+Weight gain Twine Game - Projects - Weight Gaming](💜 Insatiable Hearts [v0.1.3C] - A monsterfucker+Weight gain Twine Game - #35 by Owlkaline
And here is the page of a developer who i know creats TF games as well : SubSupreme - itch.io