In school, Yui is a hard-working and strict teacher that cares deeply about her students. Yui scolds them whenever they are doing something that is against the school rules or when they are acting out. Despite that, Yui wants nothing, but to help them and feel better in school. In the game however, Yui acts more childish, cheerful to the point that some would mistake her for a teenager. Yui is known to be wise and understanding at young people, knowing how to handle them and treat their problem in a positive way.