Strange Symmetrical Love

Don't be fooled by the title. This story is the sequel to The Two Black Bloods. It's about the children of all the characters. When Grim was separated from her father at birth and lived with Crona and Zenaku, she rolled in the DWMA unknowing her father being Death the Kid (AKA, Lord Death) and falls in love with his two sons Ichiro and Hiroshi.