a sex act where the male slides or dangles his penis into his partner's mouth while she (or he) tilts her (his) head back-resembling the act of using a beer bong
Man, my gal laid back on the bed and let me do some serious cock bonging last night!
Alternative phrase for the more commonly used "penis pump". This is due to it's resemblance to a bong, and the fact the penis is placed inside said object.
That's a cock bong man, you must have a tiny wanger.
When a naked standing man pours a beer down his chest and the recipient chugs it as it cascades off of the mans cock.
Andrew: Mike, why are you naked and soaking wet?
Mike: Because I'm awesome... and I Just got done giving this whore Diana a cock bong!