|Original Run||September 9th, 2015|
|Successor||13th Mystery Mystic Renaissance|
|Ending Song||Zenkai Strike!!|
(ep. 7-10 and 12)
Happy Fate (ep. 11 only)
Itsuka Aimashou (ep. 13 only)
Fujisaki Middle School is a very big school, but there's not enough students in it. One of the classes, which is 2-C class even has only 12 students. Though this is few and all of them usually fight a lot, they are really friendly class in fact. But everything changes when a girl, who's name is Nazo Kiriya transfers in their class... As the strange events start to show up in Fujisaki Middle School, Nazo becomes known as a curse called "13th Mystery". With the decision of Daichi Akiyama the classmates form an opposition towards the new girl.
Daichi Akiyama (秋山 大一 Akiyama Daichi)/ 1st
Voiced by: Shimono Hiro
Daichi is a self-confident, energetic and boasty 14 year old boy and the main protogonist of the series. Despite of his over-boastiness and a habit of regularly doing rash actions he truely has a leadership skills and will not left anyone in trouble. He is the one to start an opposition against the new girl Nazo Kiriya, but nearly in the end he feels sorry for her and appologises. His full nickname is 1st Hero but he is usually called just 1st.
Nazo Kiriya (桐谷 謎 Kiriya Nazo)/ 13th
Voiced by: Hidaka Rina
Nazo is a mysterious and quiet 14 year old transferred student and a new girl in 2-C class. Because of the mystical and strange events that are started to happen after her transferring in Fujisaki Middle School, she is concidered as a curse by her classmates who try to avoid Nazo and make her leave this school. In the last episode, she left the school, thinking that she brought only troubles, even though Daichi finally changed his mind and confessed his love for her. Her full nickname is 13th Mystery, but she is usually called just 13th.
Ai Hanasaki (花咲 あい Hanasaki Ai)/ 2nd
Voiced by: Murata Tomosa
Ai is a really hyper, upbeat and emotional 14 year old girl and Daichi's friend who is also in love with him and doesn't hide it at all. She will do anything to deserve Daichi's heart even if she was rejected by him many times. She usually fights with Hiroshi, but ends up falling in love with him after failing with Daichi. Her full nickname is 2nd Chance, but she is usually called just 2nd.
Hiroshi Haruno (陽野 寛 Haruno Hiroshi)/ 3rd
Voiced by: Sakaguchi Daisuke
Hiroshi is a cheerful and friendly 14 year old boy who is the best friend of both Daichi and Ai. Though he isn't unserious or air-headed, he can be incredibly naive and clumsy, so is easily fooled by Ai or sometimes by others. He often fights with Ai, but secretely has a feeling for her. His full nickname is 3rd Ally, but he is usually called just 3rd.
Kazuko Kawaguchi (川口 和子 Kawaguchi Kazuko)/ 4th
Voiced by: Kitamura Eri
Kazuko is an outgoing, polite and honest 14 year old girl who is somewhat strict, despite of her cheerful, lively and friendly personality. She is straight-forward, likes to obey the rules and sometimes tends to be stubborn. She has a habit of speaking very fast and is best friends with Kenta and Hayate. Her full nickname is 4th Issue, but she is usually called just 4th.
Kenta Hiiragi (柊 剣太 Hiiragi Kenta)/ 5th
Voiced by: Fukuyama Jun
Kenta is a cool 14 year old boy who can get angry guite easily and being annoyed by Daichi and Michiko acts disrespectful to them. He tries to seem independent and strong, but in fact has a soft and weak heart which leads him to act rough. Kazuko, along with Hayate are the only ones to know his real feelings. He is thankful to Kazuko's understanding and even falls in love with her, yet strongly hides it. His full nickname is 5th Slash, but he is usually called just 5th.
Hayate Saotome (早乙女 颯 Saotome Hayate)/ 6th
Hayate is an elegant and calm 14 year old who is the crush of the juniors. A contrast to Kenta, he is more of a confident and collected person and doesn't ever hide his care towards others, oftenly helping his classmates. However, he likes to make fun of Kenta, who doesn't get along well with him though secretely is a bit jealous of Hayate. Despite of it he has a strong bond with Kenta and beside him, is good friends with Kagene, though often gets shocked by his actions. His full nickname is 6th Sense, but he is usually called just 6th.
Nana Nijisumi (虹墨 ナナ Nijisumi Nana)/ 7th
Voiced by: Taketatsu Ayana
Nana is a distant, self-disciplined and calm 14 year old rich girl who is good at drawing and appears very cold. She may act with less emotion, but on the other side she tends to feel depressed and weak, not able to live. She sees the world in dark colors, but when coloring her drawings, she uses many different colors to make herself happier. Her full nickname is 7th Sky, but she is usually called just 7th.
Kagene Hoshizora (星空 影音 Hoshizora Kagene)/ 8th
Voiced by: Midorikawa Hikaru
Kagene is a cool, cold-blooded and confident 14 year old rich boy who tends to act cheeky and often appears with a cup of tea. He is way more friendly and outgoing than his cousin Nana, but is also rather strange and mysterious. He has a huge love for sweets and if he sees one, Kagene will turn surprisingly upbeat and excited. He is gentle and responsive, especially to Nana, although they rarely get each other. His full nickname is 8th Slice, but he is usually called just 8th.
Haruto Kujou (九条 遥斗 Kujō Haruto)/ 9th
Voiced by: Toyonaga Toshiyuki
Haruto is a rough 14 year old boy, who seems to be indifferent and distant. But behind his aloofness he is really shy, thus can't show his sympathy for harmony and peace, his kind, warm and even romantic reality. He is close friends with Kagene who often tries to help and make him more confident, but, however, he finally learns how to uncover his true self by warming up to Nana and making her feel better. His full nickname is 9th Dream, but he is usually called just 9th.
Katashi Tachibana (橘 堅 Tachibana Katashi)/ 10th
Katashi is a violent and mean 14 year old boy and Daichi's rival. No one knows how such a sporty and brutal boy can get along so well with such an excellent students like Manabu and Michiko. He is usually firm and bossy, but is also quite loyal, kind and wise, though wasn't ever truely satisfied by himself. He is also fond of mocking Hiroshi and Kazuko which leads Daichi and Kenta try to knock him out, but they always fail. His full nickname is 11th Round, but he is usually called just 11th.
Manabu Saito (斎藤 学 Saitō Manabu)/ 11th
Manabu is an intelligent and composed 14 year old boy and the second smartest student of the 2-C class after Michiko. He is usually friendly and calm, but sometimes gets terribly nervous, especially when he is jealous. His full nickname is 11th Lesson, but he is usually called just 11th.
Michiko Ueda (上田 美智子 Ueda Michiko)/ 12th
Voiced by: Chihara Minori
Michiko is a strict, stubborn and ambitious 14 year old girl, the smartest and honor-roll student, being the first of the Top 10 scorers almost always, who is also 2-C class president. She is often annoyed by Katashi, though she is great friends with him, as well as with Manabu, but doesn't notice that she is a crush of both of them. She distrusts Daichi and sometimes tries to get the leadership under her control. Her full nickname is 12th Top, but she is usually called just 12th.