Australian base system Mug

The American base system involves: first base - kissing and breast fondling; second base - manual stimulation of genitalia; third base - oral stimulation of genitalia; and home base (or fourth base) - the act of penetrative intercourse. The Australian base system is slightly different: first base - vaginal sex; second base - anal sex; third base - threesome with two males and one female; home base (or fourth base) - threesome with two females and one male.