A “Pebby” refers to that of a disposable vaping device, specifically the Flum Pebble, hence the name.
“Aye bro pass the Pebby real quick”
“Naw bro it’s dead since this morning”
the act of constantly talking about being a virgin, and how its the best thing ever.
guy: my nephew keeps pebbying at me
guy 2: hah, imagine not having sex