Guest 9015 is an evil guest that makes annoying challenges, and also tries to attack the player once hidden on one of David's place. He says (really) irritating phrases when you fail walldriver challenges. He is also very lazy.
Guest 9015 used to either wear a normal cap or be bald, but now he has a purple cap, designed by Skyfry428.
Skyfry428 has made a costume of Guest 9015 that was made from fan suggestions.