Yoshio is an otaku boy who was transported to a fantasy world after being run over in his world, and upon arriving in this new world, he discovers that he is no longer human, now he is a… Lion Man?!

Fortunately for Yoshio, in this world he can strengthen himself and become a very strong beast warrior, and perhaps, he can be the Lion boss, and with this position have his own harem of lion girls in heat.

But not everything is good in this new world, Yoshio will have to solve several problems such as the scarcity of food, the hostility of humans, and the abundance of aggressive monsters that will try to kill you if you give them the chance.