Trogs

Trogs is a purple cat encountered during the Swept Away quest, originally released as the 2008 Hallowe'en event. Trogs is Wendy's cat and players can talk to him with a catspeak amulet. Upon being asked about what it is like to be purple, he comments that he is getting used to it, although he is not sure Wendy has found a way to reverse the effect.

During the Hallowe'en event the player could talk to him to have a choice of 3 fixed conversations about Hallowe'en. Trogs would comment on your attire if you spoke to him. His comments varied depending on how many costume items you are wearing.
 * Two or more items - "Rather nice costume, that. Are you trick-or-treating this year, then?"
 * One item - "Oh, I see you're wearing one costume item! Aren't you planning on trick-or-treating this year?"
 * None - "No costume, eh? Aren't you planning on trick-or-treating this year?"

He would also tell you you can get something quick and easy by talking to the Fancy-dress shop owner in Varrock.

It is possible that 'Fraidy cat is an alternate-universe version of him.

Trogs