Orpheus

-initially a human, died, and got converted to a spiritual being with deer features by the help of xxx

-left hand man of xxx in watching over xxx's creations and making sure its balanced and continues to strive

-when he was still a human he liked haru but wasn't able to love her, when he died and became a spiritual being like haru, he fell in love with her again

-orpheus and haru are assistants of xxx

-orpheus is introverted, sweet and kind (?) 

-age is stuck in 19-20