"He spent 33 years living with the brown bears (Ursus arctos) native to the Kamchatka peninsula (...) For over 20 years, Nikolayenko followed an enormous male he named Dobrynya, forming such an easy bond that the bear would often curl up to sleep just a few feet from him."

Eventually he died of a bear mauling.

Moral of the story: it works until it doesn't.