Yui Kodai, also known by her Hero name Rule, is a minor supporting character in the manga/anime My Hero Academia. She is a member of Class 1B and is mostly known to be very quiet with no signs of a change to her expression.
She is voiced by Yurianne Eve in the Japanese version and Madeleine Morris in the English version.
Yui is actually known to very silent without another word said or any expression she would offer as a sign to what she feels. For a hobby of saying "hmph" or "mm" when she eats in a very happy mood, despite she does happen to talk rarely.
Nevertheless doesn't mean she has feelings and does care about her classmates when the incident during the training camp happened. She is mostly considered as a Kuudere due to her quiet demeanor and personality.
- Size: Yui can alternate the size of any inanimate object at will if she has made physical contact in the process. Her quirk can only activate if all fingertips pushed together after physical touching said object.
- Her entire appearance and name were once used for Mount Lady's development as one of the main characters during the prototypes before it was scrapped. Later on it was decided by Kohei that Ochaco Uraraka would be the main female lead as Yui would soon exist as another character.
- Even after both Yui and Mt. Lady existed as major supporting characters, Yui's Quirk is somewhat similar to Mt. Lady's in comparison. But the difference here is that Yu can grow her own size while Yui can change any size of an object.
- Unbeknownst to Yui is that during her middle school years and even after graduating, many groups of boys started a fan club for her. Though any reason for it is unknown, it's possible the boys from different classes, including hers, were attracted to her.
- Her hat's design on the crest has an similarity to one of the famous tokusatsu Ultraman heroes, Ultraseven. Funnily enough her entire costume's coloring and design severely matches in comparison to him.