Giyu always wears a stoic and unbothered expression on his face. However, he has a reserved personality and a very strong sense of justice with no tolerance towards those who don't know their own limitations and throw away their lives. Beneath his seemingly unemotional and aloof attitude, Giyu suffers from an inferiority complex which he developed since his participation in Final Selection. It gets severe to the point where he contemplates abandoning his position as the Water Hashira.(Wiki)