as far as the alien is looking like a sexy earth girl or in disguise like a sexy earth girl like shown in MIB), I would not mind sleeping with them
it might depend on what kind of an alien that person is - whether legal alien, illegal alien or resident alien..
Remember the tv miniseries V ? If you tried to make love to those aliens they would put you on a platter and eat you
Oh wow... how wrong this reply is going to be... Sounds freakin' fantastic! No grinding down there w/ teeth + a place to set the beer. Why would I wanna sleep with the alien?!
I wouldn't sleep with an alien, no way ...you could make a lot of jokes about it, but I think it would be a big trauma for me