This is a buff version of Pumkat, a halloween cat character originally designed by the artist, acstlu. The 3D model of this character was created by MrBalrog. I've first heard about this character since last Halloween.

Muscle Base Model by NAMEII
https://sfmlab.com/project/30316/

Pumkat by MrBalrog, Personb718 (FBX version)
https://sketchfab.com/3d-models/pum.....2546e0d0988029
https://mrbalrog.gumroad.com/l/pumkat

Model edited by JayBFoxxo

Stage by まぁぼ
https://bowlroll.net/file/210698