Finger: Digits on the hands.
Bang: English slang for to have sex.
Fingerbang: to have sex using fingers, via making words on the keyboard, to express words of sexual intent onver the internet.
2) the name of the boy band Stan, Kyle, Cartman & Kenny made that Wendy joined
3) to pleasure a woman with your hands in her pussy or ass or even to a man via the ass
"I'm gonna finger bang, bang you all through the night. I'm gonna finger bang, bang into my life.
I finger banged Michelle last night. She obviously liked it cause she giggled and moaned during it.