I played a rated rapid versus a relative new account. The opponent overestimating his position and his chess-abilities, wrote in the chat without being called for right after the move 11. Ne4-Qg6: "Gg. Rematch?"
However karma got the best of him, as you can see it here.
The moral of the story is: "Be nice or at least do not look silly by losing a game where you shout to your opponent: "You are done Wuhahahaha! Rematch?"