Alien comet creature (Starret)
So like she was this egg thing in a comet and when it landed on earth she hatched bc of the heat from falling, but she's super small because the comet egg lost pieces as she fell.
She constantly has less energy as she isn't on her homeplanet, but she doesn't need as much anyway
She's about the size of a ferret but can run near 100MPH
She (like others of her species) have no mouth as they get their energy from the moon, but she can speak her own language through telepathy, as well as other noises. This ability is so strong it appears she is speaking to everyone around.
Im not sure what to call her species, if you have an idea tell me though! I might make a species sheet for them.
Edit: They're called Starrets