The focus of Chapter 3. Keis older sister Yuu is a cheery girl who never hesitates to make friends. Although she appears to be a little ditsy she carries an avid interest for just about everything making her very knowledgeable on a variety of subjects. As a result she like her sister garners a lot of attention from many guys. However whether its being oblivious or just nonchalant she doesnt seem to mind being friendly with all of them.