|Name in Japanese||瀬戸 燦|
|Debut (Anime)||Episode 1|
|Debut (Manga)||Volume 1|
|Appears in||Anime, Manga|
|Voice Actor (Japanese)||Haruko Momoi|
|Voice Actor (English)||Alexis Tipton|
|Affiliation||Isono Junior High School|
Sun is a beautiful fair-skinned girl with waist-length tan hair that has square bangs, light brown eyes, an above average figure and a relatively large bust.
Sun is a calm, average and smart girl for her age who is most likely the only one in her family who has a clear head.
Powers and AbilitiesEdit
When push comes to shove, Sun demonstrates a great deal of inner strength. Sun often uses her Song of Heroes to power Nagasumi Michishio up in battle situations. She has shown a great deal of swordmanship, which she was taught to by Masa.
Sun decided to face her fears and take on the responsibility of taking care of Nagasumi Michishio as her husband, although it doesn't make it easy on her due to almost everyone in the Seto group (except Ren Seto (Sun's mother) and Masa) who are against their union. However, as the series progresses, she truly falls in love with Nagasumi.
- The name Sun means "sunshine" (燦) in Japanese.
- Sun's surname Seto means "swift current, rapids" (瀬) (se) and "door" (戸) (to).