To be honest, I'd probably just watch porn with them and choose a BDSM one just to test the water on their reaction. If they seem cool with it, I'd probably casually bring it up that you'd like to try it - if they say no, they say no but either way, you find out
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I hear that song but something is wrong,
my mind’s a million miles away,
oh, everybody’s going to the floor,
maybe I don’t want to dance anymore,
don’t want to dance anymore,
how can you dance the pain away? <3