Random Anime/Manga Character Headcanons

Unnamed Painter {Happy Sugar Life}

Canon facts:
-Was a painter.
-Lived alone in the same apartament building that Satō and her aunt.
-Was a smoker.
-Meet Satō and wanted to paint her because of her lack of emotions.
-Wanted to kill Shio because she made Satō feel emotions.
-Got killed by Satō.

Headcanons:
-My name for him would be Daisuke Katō.
-He was Asexual and Aromantic . It's something that poped up in my head when Satō asked him about love in one of episodes and she simply said that 'it's weird'.
-Didn't had any friends or family. It can also explain why no one cared much after Satō killed him.
-Painting was just a hobby of his.
-His true job was in the office.

I really can't tell more about him due to his lack of screentime or background.
Maybe you have some ideas?