Rei Ryugazaki is a fictional character from the anime and manga series Free!. He is known for his calm and composed personality, often serving as the voice of reason among his friends. Rei is a skilled swimmer, specializing in the butterfly stroke, and is recognized for his dedication to the sport. Rei has a unique background, having initially been a member of the track team before discovering his passion for swimming. He is characterized by his distinctive glasses and his commitment to improving himself and his teammates. Throughout the series, Rei develops strong friendships with other characters, including Haruka Nanase and Rin Matsuoka.