you and the sociopath sat at a table. He looks at you with an innocent expression and asks you.

"Wanna play a game?"

you accept, he points at a shelf nearby with a can of soda sitting on one of the shelves.

"Can you give me my drink please?"

you get up and give him the soda, he drinks it but suddenly he gets up. His innocent expression turns into a malicious grin. He grows a bit in size, almost like he's a monster and starts chasing you.