Itto Takatenjin (一戸高 天神 Takatenjin Itto) is a 1st year in class B and a member of the Swimming Club.
For the school uniform he wears, this consists of a navy blue jacket he has unbuttoned over a white shirt with an orange red colored tie. He has a black belt and silver buckle around the top of his brown chequered pants, and also maroon colored, laceless shoes.
The swimming club's rookie and mood maker. Most people have a hard understanding what he is thinking. He usually has his head in the clouds, with very selective knowledge and is easily distracted. He can also be quite unaware of his words and tends to sound harsh, especially towards his captain.
Similarly to Hozumi, he has a love of swimming and water. Unlike Hozumi, however, he's very impulsive and does things without thinking because of his love, such as opening a window when it was raining heavily because Hozumi said that it might make a pool in the classroom.
Despite all this, he is a surprisingly smart guy.
Itto shares a love of swimming with Hozumi, making them close friends. They are often seen together and are almost inseparable, as joked about in a 4koma.
Hozumi cares about the well-being of Itto, as seen in the ACTORS -Drama Edition- East when he gives Itto his hoodie and some hot tea after the both of them 'swam' in the cold sea. In the same track, they go to an aquarium Hozumi gets splashed by water because of a dolphin. Despite being the one who suffered from the splash, he asks if Itto is alright.
Itto considers Hozumi to be someone that takes care of him.
Takato is Itto's swimming captain. They get along well, but Itto has a habit of saying rude and insensitive things about Takato. He also complains that Itto never calls him "senpai."
Itto is very fond of Minori and considers him a close friend, balantly telling Uta Outa in Deluxe Dream Edition that he liked him. Itto seems unaware that Minori doesn't share the same feelings.
They are classmates and Itto considers Kai a friend, and the feeling is reciprocated. In ACTORS Drama Edition East, Kai suggests that they, along with their senpais, Mike Enjoji and Hozumi, should have meals with eachother if they ever run into eachother in Hokkaido. Itto is excited by this and asks if Kai has curry, which he doesn't, but Kai promises to have a big curry party.
Itto's relationship with Hozumi and Kai's relationship with Mike somewhat mirror eachother (two senpais with an unbreakable bond with one of their kouhais).
- The name Itto means "heaven, sky" (天) (it) and "god" (神) (to).
- Itto's surname Takatenjin means "tall, high" (高) (taka), "door" (戸) (ten) and "one" (一) (jin).