Green’s Dictionary of Slang

(orig. US campus) group sex in which a number of males have sex with one woman; similarly of male homosexuals; also attrib.

1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 56: bunch punchn Group sex in which a number of males have coitus with one female.
1997		Solar Project ‘Zeitgest’ 🎵 on ...in Time [album] Group grope, bunch punch / Gang bang, daisy chain.
1998		‘Mrs Babymash Snr’ ‘Sliterary Success: Write Up My Alley’ Part 1 on alt.freaks 🌐 This Roman masterpiece is about two depraved date-packers who almost snuff it when an earthquake brings the roof down on their bum-bandit bunch-punch bordello.
2002		J. Burkardt ‘Itty Bitty: Nonsense Rhymes’ Wordplay 🌐 bunch punch (group sex; a gang bang).