Surprise!!, it has nothing to do with guys stalking and/or doing sexually deviate things to women/girls.
the act your dog performs when he/she pokes you with their snout (usually under your arm) when they want your attention
Damian: Dude, what's your dog doing with his nose, I'm trying to watch the game..??
Chucky: He's sharking you. He wants you to throw his toy for him.
Damian: Yeah, well, if he does it again, I'm gonna throw a harpoon at his sharky Amityville ass.....