You noticed the mirror

Staring in front of yourself, you see your reflection, and behind it, the reflection of Anastasia and her two friends. Riley's grinning, Anastasia looks like she's trying not to laugh, and Sarah hopefully hasn't noticed. As if in response to your hope, she makes eye contact with you, winks, and mouths "keep going."

You can't just keep going, surely, but it would be even worse to walk over there now, after they all saw you doing that. Maybe if you actually do it, they'll be too embarrassed to say anything. Or if you pretended you had known the whole time, and were just joking with them? Your chest and pussy make three votes for whatever option involves you cumming. Your brain tries to veto, but it feels like your body is sending echos of pleasure back up, making it hard to think.

Masturbating with friends isn't real, it's the sort of thing you'd see in a porno. But then, that's what you would have said about bathing together too, and you don't have much experience with friends, and none with people like these. Maybe they do this all the time? The other three voters emphatically support this idea.