|Height||178 cm (5'10")|
|Weight||72 kg (158 lbs)|
|Occupation||2nd Member of the Mekakushi Dan|
Sayori Ishizuka (Young)
|Manga||03. Kisaragi Attention|
|Anime||01. Jinzou Enemy|
|Novel||カゲロウデイズ II -a headphone actor-|
|“||It's such nice weather. But I wonder where this is. There's a deer I've never seen before.||”|
Kousuke Seto (瀬戸 幸助 Seto Kōsuke) is the second member of the Mekakushi Dan.
- Seto is a young man with short black hair and hazel eyes. When he was young, he wore a white hoodie with golden trousers and purple sneakers. Now in the present day he is always seen wearing a dark green jumpsuit with a brown belt and dark green sneakers. The hoodie on his jumpsuit also has a pair of goggles attached to it, which leads Kano to call him a "giant frog". He also wears a yellow clip on the left side of his head. His sleeves and pant legs are rolled up, showing the white inside of the suit.
- In Mekakucity Actors, he wears a black shirt with a red neck underneath his suit and shoes that appear almost black.
- In Summertime Record Seto is seen wearing his white hood and underneath a yellow shirt, but still using the pants of his green jumpsuit.
- Seto is a kind-hearted person, first visible through his behavior while befriending Marry and inviting her to join the Mekakushi Dan, while everyone else in Marry's life had bullied her. As a result of his kindness, he also makes friends easily, like the first time he met Shintaro. He is also good friends with Kido and Kano, as they all came from the same orphanage, and lives with them together in an apartment. He often wanders off to explore new places. To gain money for living he works as a florist at a shopping center, and also in various other jobs, such as traffic control and delivering newspapers.
- He dislikes his Eye Ability, because he sees it as a power where one "steals" with glances, without needing communication, so he rarely uses it on anyone. He first discovered his ability to speak to animals while wandering through the forest before he ran into Marry.
- Stealing Eyes (目を盗む Me o Nusumu): Seto has a power known as the "Stealing Eyes" ability, which allows him to read information from the target. He is also able to speak to animals using his eye ability. However, even though he is able to understand animals, the animals cannot understand him because to them, he still speaks human language.
- Souzou Forest
- Konoha no Sekai Jijou
- Kisaragi Attention
- Yobanashi Deceive
- Lost Time Memory
- Ayano no Koufuku Riron
- Otsukimi Recital
- Yuukei Yesterday
- Outer Science
- He has a pet hamster named "Hanao". The hamster may know something about eye abilities, as he calls Seto a monster. It also appears to know about Azami.
- His favorite type of girl is someone like Yachigusa Kaoru.
- Like Kido and Kano, he is referred to with his last name rather than his first name.
- His white hoodie was a gift from Ayano when they were younger, but he gave it to Marry upon meeting her.
- He usually ends his sentence with "-ssu", a way to shorten desu, a Japanese polite copula.
- Because Seto has a lot of part-time jobs, he was designed to wear something comfortable to work around, as suggested by Shidu.
- His dog's name is "Hanako".
- Seto's designs had to be corrected the most when the anime production team presented the rough character sketches. According to Shidu, he looked like a whole new character.
- Seto is the third character to appear in the anime.
- "Encounters are produced through coincidences." ( To Marry in 23. Kagerou Daze VI )