Specialty: Freestyle
Height: 155cm (High☆Speed!) → 175cm (Free! Seasons 1-2) → 177cm (Season 3)
1st year university student
Weight: 63kg
Birthday: June 30
He and Makoto are childhood friends. In middle school, he met Ikuya and the others and joined the swimming club, but after various circumstances, he quit swimming. He started again in high school and continues swimming in university.
Toudai University
He has a cool personality, is taciturn and unsociable. He is also quite an individualistic person who goes at his own pace.

Specialty: Freestyle & Butterfly
Height: 177cm (Seasons 1-2) → 179cm (Season 3)
1st year university student
Weight: 68kg
Birthday: February 2
At some point during elementary school, he transferred to the swimming school where Haruka, Makoto, and the others were. Before entering middle school, he went to Australia for swimming training. He returned to Japan once during high school, and after various circumstances, he is now in Japan.

Prone to tears
He has a passionate dedication to swimming beyond that of most people, and a personality with a strong sense of duty and honor.

Specialty: Backstroke
Height: 168cm (High☆Speed!) → 183cm (Free! Seasons 1-2) → 184cm (Season 3)
1st year university student
Weight: 73kg
Birthday: November 17
He has been childhood friends with Haruka since before elementary school, and they attended the same elementary, middle, and high schools.
He attends a university in Tokyo in the sports education department.

He has a kind and caring personality, often looking after Haruka. As a good understanding of the taciturn and unsociable Haruka, he sometimes acts as his spokesperson.
He has a relaxed and gentle way of speaking, with a kind tone that reveals his caring nature.

Birthday: March 3
Height: 150cm (1st year middle school) → 176cm (1st year university)
1st year university student
Weight: 42kg (1st year middle school)
In middle school, he was together with Haruka, Makoto, Asahi, and Kisumi, but in his first year of middle school, he went to America with his older brother. He is now in Japan.
Sourou Gakuin University
He has an intelligent and composed tone, yet it carries a somewhat delicate and emotionally sensitive, boyish quality.

Birthday: January 20
1st year university student
Zodiac Sign: Aquarius
Height: 181cm
He met Ikuya in America, and after returning to Japan, they entered the same high school and then the same university.
Sourou Gakuin University

Specialty: Butterfly
Height: 155cm (1st year middle school) → 179cm (1st year university)
1st year university student
Weight: 48kg (1st year middle school)
Birthday: April 18
In middle school, he joined the same swimming club as Haruka and the others, but transferred schools partway through.
Toudai University

Specialty: Butterfly & Backstroke
Height: 185cm (Season 2) → 186cm (Season 3)
1st year university student
Weight: 76kg
Birthday: September 14
He has been friends with Rin since elementary school. At that time, he had no contact with Haruka and the others, but they connected in high school and are now good friends.
Seka Kyoritsu University

Height: 157cm (High☆Speed!) → 182cm (Free! Dive to the Future)
1st year university student
Weight: Unknown
Birthday: May 26
He is friendly, cheerful, and frank, with a lighthearted way of speaking that allows him to quickly get close to anyone.
In middle school, he was with Haruka, Makoto, and the others, but he was in the basketball club. However, they reunited in high school and remain good friends in university.
Toudai University
In middle school and university, he played basketball. In high school, he was separated from Haruka and the others, but they reunited through a certain event.