There isn't a single person in Sakuradamon High who hasn't heard the legends about Seiji The Mad Dog Sawamura's demonically powerful right hand. His reputation makes it fairly difficult for him to approach girls, and after being rejected 20 times straight, he half-jokingly vows to finish high school with his right hand for a girlfriend. Much to his surprise, after waking up the next morning, Seiji discovers that his demon right hand has mysteriously turned into a miniature girl, Midori Kasugano, who reveals that she has had a crush on Seiji for the past three years. Because their situation is not ideal for either of them, Seiji attempts to return Midori to normal. But after causing a big misunderstanding at the Kasugano household, the pair decide to keep their predicament between them until a solution is found. Thus begins an odd relationship, and what could be the only chance for Midori to finally be with the one she loves.

Another version of Miracle Train: Chuo-sen e Youkoso. The first version of the Miracle Train project focused on the stations of the central Chuo line, while the new anime and related stories deal with the Oedo subway line. As a result, the anime will feature a newer cast of characters—specifically, Fumi Roppongi, Rintarou Shinjuku, Izayoi Tsukishima, Iku Shiodome, Saki Tochou, and Itsumi Ryougoku.

Yukiteru Amano is a shy middle schooler who regularly keeps track of what he does in his daily life by writing down all of his activities on his phone—a digital diary. Despite having no friends at school, Yukiteru is frequently seen talking to his supposedly imaginary friends Deus Ex Machina, the god of time and space; and Deus' servant, Mur Mur. One day, Yukiteru wakes up and discovers that certain events of his day are preemptively displayed on his cellphone. While initially dismissing it as a coincidence, he slowly realizes that the incidents written in his phone actually take place in the near future. After spending the day benefiting from this new asset, Yukiteru learns that his classmate Yuno Gasai possesses a similar diary. As the two team up to defeat an odd pursuer and head back to their respective homes, Deus Ex Machina explains that they—alongside 10 other contestants—have been drawn into a survival game whose victor will become the deity's successor. With no other options, Yukiteru and Yuno must use their cellphones—now called Future Diaries—to survive this unforgiving battle royale.

The 11-year-old Marui triplets could not be any more different. The oldest one, Mitsuba, is sadistic and kind of mature for her age. The middle one, Futaba, is perverted and very athletic and has the strength of a full-grown man. The youngest one, Hitoha, is generally very quiet and gentle but when push comes to shove, she might just be the strongest, the most perverted and the most sadistic out of the three. The three are all in the same class, led by the newly graduated teacher Yabe Satoshi. He usually gets pushed around by the girls and, on occasion, abused but the triplets also try to lead him and the new school nurse, the clumsy Kuriyama Aiko, together. However, Yabe had no intention of dating Aiko and the methods the triplets use to accomplish their goal are highly unorthodox...