This is a sexual term referring to a particular sex act where a man receives a blow job from a woman, cums in her mouth, and then the woman (or could be a man) pretends to swallow, then turns to embrace her partner in a passionate kiss, thereby open-mouth kissing him with his own cum in her mouth. Hence, San Francisco Switcheroo (almost gay, not quite)
Man: You gonna swallow right?
Woman: Of course
Man: You better not pull a San Francisco Switcheroo on me cause I'm not okay with swallowing my own cum.
Woman: Of course
Man: You better not pull a San Francisco Switcheroo on me cause I'm not okay with swallowing my own cum.
by kyrie calavera February 12, 2007
When your partner has fallen asleep after sex, quietly slip out and exchange places with a friend who's the same sex as your partner (or the opposite sex if you're homosexual). After they've gotten comfortable together, call your partner or knock on the window. Surprise!
by Yeah_I_dont_care February 01, 2011