My friend drank too much, and started acting like an ass.

　　jerk/asshole

　　The waiter was such an asshole I decided not to give him a tip.

　　kiss one's ass

　　He kissed the teachers' ass all year.

　　kiss my ass

　　piss sb. off

　　An aggressive driver who is angry at another car may yell kiss my ass out of the window.

　　jackass

　　I hate it when a party was ruined by somebody being a jackass.

　　party boiler