This bear started out as a regeneration experiment run by the Qmay organization. The whole point was to develop enhanced healing abilities, which definitely worked—he can bounce back from severe injuries in minutes. There's a famous incident where he took a knife wound that should've been fatal, only to heal right up.
At some point he got loose after a car accident. That's when Ito found him and eventually took him in as her own. The two have been together since.
Content compiled by AnimeList.moe from publicly available sources.
