Green’s Dictionary of Slang

quick, spontaneous intercourse, with the implication that only the man will achieve pleasure.

1996–2003		Ken Emerson ‘Rev. of Millie Jackson, Get It Out’cha System’ at RollingStone.com 🌐 Numbers like [...] ‘Bip Bam Thank You Mam’ (which dismisses a Johnny-come-quickly lover as ‘a regular one-minute Sam’) cry out for more sass than Ann Peebles can summon.
2005		posting at advicechick.com 8 Nov. 🌐 It’s really bothering me to think this same guy could be soooo eager to see me every night, then with one bip-bam-thank-you-ma’am he is a stranger.