Inspired by the movie Requiem for a Dream, ass to ass is a sexual position where each partner simultaneously insert a double-dildo into his/her anus. Each partner is then penetrated to adquate length of the double-dildo so that they become "ass to ass."
Two heroine addicted prostitutes insert a double-dildo into her anus while a crowd of men cheer them on and a mysterious man named Uncle Hank yells, "Ass to ass!".
-Requiem for a Dream
adj. A statement of one's level of commitment or enthusiasm superseding balls deep. Though not physically possible, it paints a damn vivid picture of how far one is willing to go.
Boy 1: How long have you been sitting there playing Call of Duty?
Boy 2: Four days, sixteen hours and three deathmatches.