1.Imagine a pair of breasts swinging behind your penis - Breasticles.
2.Maybe you're undoing a girl's (whom youve just brought home for the first shag) bra and find a pair of testicles where her breasts should be - Breasticles.
Can also be used as a derogratory term in the same style as "Jep, you tit!" or "Bollocks!" e.g "Jep, you breasticle!" or "Breasticles!"
"Nathan, you breasticle!!"
Mark: Not much man, just found out last night that I have a breasticle.