RIO Izumi

From Animepedia

Rio Izumi a shinigami who was previously partners with Meroko. In the anime he is depicted as a villian trying to capture Mitsukis soul. In the manga he is accually a friend of hers.

When Izumi was little his father died, causing his mother to go mad, beating Izumi for looking like his father. Boyfriends of his mother would often leave because she had a child laging around her, so that fed her anger. One day when Izumis scars were barely visible his mother took him to the town. While passing by railroad tracks Izumi thought of a way to make his mother happy. Noticing a train coming by he ran to it, ignoring his mother trying to stop him. As he was hit he thought he saw a glimpse of her smiling. Later on in the manga series he is assigned to take her soul.