8 XXX : SexInFrontOfOthers

I'm wondering about the guy with his hand on her ass. In this situation, do you just join in like that or do you ask permission first? Is the guy on the ground returning the love or cock-blocking?
Where does this happen?
why is there a decapitated hand covering her pussy? lol I was half asleep from just waking up, yeah I see where the hand is coming from. Sorry about the confusion thanks for the help guys.