Why does my girlfriends adopted cat follow me everywhere i go in the house. he even wedges himself between us.

she's had him about 3 months, he's neutered and a little over 2 y/o. i believe he's an American short haired tabby. He's kinda spooking me out. When I go in the bathroom he's in front of the door when i come out. It's that serious!!!! He'll even continuously try to lay on my chest even after i push him away... and I've only fed him 2 or 3 times since she had him.