When one man proceeds to give another man (usually his gay boyfriend) a blowjob, but smears cake frosting all over the recipient's penis and licks it off. Sometimes the frosting mixes with the recipient's cum.
Dude, I gave Bobby a lovely Cupcake Charlie last night. I used vanilla frosting on his cock, and then he jizzed in my mouth and it tasted really good!
Lovely. Was it any better than the time Johnny sleepwalked into your room and fucked you up the ass?
Actually, yes.