Green’s Dictionary of Slang

the female breasts, esp. when large.

1963–74		B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 85: ‘Fun-bags? What are you driving at?’ ‘Fun-bags! You know top bollocks!’.
1985		B. Humphries Traveller’s Tool 51: The way she brushes the cigarette-ash off her impudent and lightly ensheathed fun-bags.
1985		‘Jennifer Blowdryer’ Modern English 77: tits (n): Funbags.
1997		Roger’s Profanisaurus in Viz 87 Dec. n.p.: fun bags n. Breasts; knockers; thruppennies (qv).
2003		www.thepantsman.com 🌐 A blonde busty wench [...] sporting a low-cut tight leather top exposing half of the most impressive funbags you could ever see.
2005		L. Redhead Rubdown [ebook] I became desensitised to funbags, completely sick of spadger.
2013		F. Bill Donnybrook [ebook] ‘After your nappy-headed bitch gets on her knees, takes that shirt of hers off. Lets me service them fun sacks while she tastes my ugly stick’.
2017		T. Spicer Good Girl Stripped Bare 187: You must massage your boobs [...] Hours of fondling your funbags.
2019		Twitter 22 June 🌐 And verily the Lord did decree [...] ‘thou shalt NOT have fulsome fun bags AND have less body fat than 20% - without surgery’ .
2022		https://tubesafari.com 🌐 Mature blonde Carson Carmichael with giant fun bags is seducing boy on the school desk.