With the Killer Vegan set of skills killing cute animals results in a rather nasty debuff getting applied to your character. Which creature's deaths will trigger this?
Related: How does Killer Vegan skill work?
Monsters designated as 'animal' (rather than vegetable, undead, demon, etc...) may invoke the Fallen Vegan debuf. Also, eating non-vegan foods (meats, cheeses, eggs) may invoke the debuf.