Smothering, choking, garroting, underwater, latex masks, plastic bags, manual, either with or without safety limits.
If this does get added please add heart sounds as described in another thread as breathplay can do crazy things to one's heart and the two often go hand in hand (i.e one does breathplay to make their heart speed up or slow down).
Eventually when the underwater lab gets added, maybe include an air gauge for non aquatic characters. Moaning/grunting becomes more frequent as they lose air, and they cough/pass out if it becomes empty. (Before safely system kicks in) Also include a drowning fetish for character preferences?
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