Hiroyuki

Race: Dog

Hiroyuki is a pure breed mongrel and the pet of Genzo Shibata. He accompanies Genzo everywhere he goes, including his fights in the ring, there Hiroyuki will join the fight and do special moves with him. When he was transported to a different world and time with Genzo, his species was unknown and thus he was considered a rare species, so people wanted to steal and sell him.

(Source: Kemono Michi Wikia, edited)