He appears to be 43, but he's 273. He became immortal in 1798. He was born in 1755. He has a beard. He fell in love with his best friend's wife and then killed him so he could be with Alice. He got her pregnant, but Death took his baby and made Michael immortal as punishment. When Alice left him ten years later the baby died, he didn't handle it well. After that, he spent years chasing Death, many times he tried to confront her to end the curse of immortality, but it didn't work. He was about to give up until he met Elly.
Michael is a serious person; he rarely laughs. He has already lived too long and only wants to regain his immortality. He takes keeping his identity hidden very seriously so that no one discovers what he and Elly are. This is one of the main reasons he fights with Elly a lot. It isn't until nearly the end of the radio drama that he begins to open up more to Elly and tells her his past.
Note for the voice actor: This character will have to portray almost every emotion a human can feel and also narrate. Michael will have two chapters that explain his past, and he will narrate them himself. Some scenes include fights, growls and sounds of pain, crying, screaming, and more.