Find a masturbation party to attend.
I don't like to post negative things but this is a reason we don't typically attend house parties that invite single guys. In fact, we haven't been to one where single guys have been invited with the exception of one attending with another couple and he is the couples responsibility. If they leave, he has to leave.
All house parties have different rules but I'd rather let the Chihuahua hump my leg than see a single guy sitting on the couch beating off while we were trying to play.
I think a very small percentage of couples like to see a guy beating off. Going out on a limb here but maybe 1 in 100.
Don't be that guy.