Grust

Grusts are a species  of humanoids that look like preschoolers always wearing tracksuits. They  are all preschoolers, and they don't age at all, so they keep themselves 100% preteens, because they are part of their own group of mammals, not hominids, apes, nor any primates, despites a comic series about them, but are part of a group of mammals known as moswanginae.

 They are extremely peaceful and gentle towards all sapient species and sapient beings, except  vampires  due to bloody conflicts with them. They are omnivores that feed on the same kind of food as many other sapient species and sapient beings.