- Only to enter in depresion when they realize a big source of anime has disapeared... I mean the ones outside of the district that survived of course...
- Both have names starting with S
- Both have a name related to plant life
- Shion's eyes change colour, Seishirou loses an eye
- Shion has a snake scar, Seishirou acts like a snake
- Nezumi and Subaru have a lot in common, for example, they both have dark hair and they both have eyes.
- Asano Atsuko said that she got the inspiration for No. 6 from many sources, and I bet I can guess what one of them was ;)
Come to think of it:- Seishiro had a loved one who had a sister - and killed this sister- Kamui had a loved one who had a sister and was predestined to kill her... before his and his Twin-Star fates were exchanged!