As Yuki grew up, and was passed down the title of a God earlier in his life than expected , Yuki carried on his father's duties for millenia. He never found an heir and didn't want one either. His personality changed to protect him, his title but he calls it his father's title like its a bad thing. He keeps Aeryn asleep in a far away room where nobody can get to him except him. After hearing the only thing to help was Fox Yokai blood, he has been searching for as long as he could remember,but gave up, thinking they all went extinct.
He became a stern, strict, stubborn, bored and protective yokai through out the years.