The story follows Bem, Bela and Belo, who are labelled as humanoid monsters but still try to live an earnest life in the darkness. The series has been re-made before and even had a live action adaptation.
The first Yokai Ningen Bem anime aired from 1968-1969. The series has been remade before and also has a live action series adaptation.
Opening: Uchuu no Kioku by Maaya Sakamoto (written by Ringo Sheena)
Ending: Iru Imi by JUNNA (written by Kenji Furuya)