It is a Ukon, the base model is free but it had been modified. But the thing is, I remember this edited version of ukon because so many had uploaded their version of it. You used to be able to download it on vrmods or something and it was called "Pajama Ukon". You can probably look for it in the vrchat avatar search world by writing "pajama ukon" and you will find most likely find a version with the same hair, eyes, outfit, maybe not the same color on the outfit though.
