Dark is dating Lucifer the king of the underworld and being king means Lucifer is busy and has meetings so when one day when one Lucifer was at a meeting and Dark was in the castle by himself someone put a postion in dark's drink that deages Dark but dark didn't know that and drank it but right after that he wasn't feeling so good but he thought if he laid down the pain will go so he want to take a nap so when Lucifer came back and walked into their room and he saw a baby their instead of his lover but the baby was dark...start from there