It's my girlfriend's birthday on Monday and she is a keen player of the game and she LOVES CATS. Can you have a cat enemy of some kind? (preferably a tabby, as her home cat she sees rarely now, called Lady, is a tabby) It would literally make her day. And mine. I love cats too.
Suggestion for it: Maybe it can not be damaged by weapons but take damage from the health orbs of other enemies when the cat goes near it (only love can destroy cuteness). So you have to lead it to other enemies so it gets near enough for the health orbs to attract to the cat and damage it. But rather than 'kill' it, when it reaches zero HP it just stops attacking / scratching you (and it could do surprisingly lots of damage, because cat scratches really bloody hurt!) and just kind of wanders around (maybe even follow the player, and maybe then attack nearby enemies AKA Wolves in Minecraft). And also, maybe it can be sleeping until a player gets a certain distance away. Maybe there can also be an ingredient that can be found that's "catnip" (from a plant of some kind, as catnip comes from a root) that you can drop and the cat will be attracted to that and not attack the player. Once 'defeated' it would be great to be able to name it (if it follows the player around afterwards). Oh, and it SHOULD NOT be found in desert areas, as I know from experience that cats HATE sand. Maybe they can be really rare too, because usually they will be away from battle areas sleeping.
For reference, a picture of the girlfriend's cat.
With ears folded back (she really likes that):
For added reference, a top down view for if it's needed: