there's a game developer on itch.io called Heazhan. They've got a few different games that have breathplay and asphyxiation as the main theme.
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is the most recent one of theirs I think. I did a quick search but I can't find a link to this other website they have (it was in Japanese I think( but that website had links to a game where you choke out a girl, a game that was more like a quick proof of concept where 3 girls are hung, and one that was my personal favorite where there is a girl in a bathtub that you can drown. I get the feeling that game was either an inspiration for or at least influenced the Girl's breath holding contest. Out of all of them, Breath holding contest has the most content.