Abuse-Sir is a fluffy artist who was active from 2015 to 2016 and was mostly known for arguing in the comment section with Santanon. Around February 2016, he was banned from fluffybooru after having conflicts with Santanon and insulting the moderators (particularly Aichi), Abuse-sir was perma-banned for continuing to argue anonymously with the moderators while ban evading and harrassing users anonymously. Feeling outrage that he lost his account, he demanded the mods delete almost all of his uploads because he didn't want fluffybooru to get any ad revenue for his pictures. Fluffybooru doesn't have any ads and has never received any ad revenue. Some of Abuse-sir's artwork can still be found on other websites. As his name would suggest, Abuse-Sir strongly leaned toward abuse, with a particular focus on unjustified abuse on innocent fluffies.
Abuse-Sir is notable for co-creating the concept of the litterpal along side the artist Big_Baybeh; although he has tried taking credit for older ideas by slapping a new name on them. A litterpal is an quad-amputated fluffy, typically brown, who is kept in a box with only its head out, and forced to consume the waste of a domestic fluffy. It is used as an alternative to the litterbox, as the litterpal's own waste remains in the box.