"My name is Tadakuni. I live a normal life, attending a normal school, in a normal town."
Tadakuni is the ‘straight man’ of the main trio, and is classmates with the other two at Sanada North High. They usually hang out at his house after school. He also works part-time twice a week at a pizza restaurant, and has a violent younger sister whom he hardly talks to. In the past, he was a member of the group acting as Rubber Shooter.
Of the main three, he appears the least in the whole series despite being introduced as the main character (the in-series joke is that this is due to his "ordinary" appearance and personality).
Not much is known of Tadakuni's past prior to the main storyline. As a kid, he attended East Yada Elementary, where he first met Yoshitake. Along with him and others, he played the role of Rubber Shooter. He later met Hidenori in middle school.
Tadakuni is a slim teenager of around average height. He has black eyes and relatively short black hair with medium-length bangs. He is usually seen in the North High school uniform. Unlike his friends, he is often seen appearing in casual clothes outside school. When working part-time, he wears the standard Pizza-Le uniform.
Tadakuni often acts as the ‘sane voice’ of the group. Despite his protests and disapproval, though, he usually ends up getting involved in Hidenori's and Yoshitake's wild ideas. He’s creative in his own way, being good at making up stories that notably excite the other two (and his sister).
Since he doesn’t have the loud, quirky personalities of his friends, he easily gets side-lined when they take centre stage. This is a running joke in the series, since he was introduced as the main protagonist but ends up getting far less screen-time than quite a few characters (he's even jokingly referred to as "Tadakuni's sister's brother").
For the most part, Tadakuni seems to be quite normal, although he does have a knack for reading a situation even if he’s not actively part of it (most notably in his dealings with Yassan and the overly self-conscious girl). When it comes to his relationships with his friends, he tends to overthink about their view of him and sometimes worry that they aren't close enough.
"Swordsman Tadakuni" is, according to Yoshitake, a warrior on a journey to become the world's greatest swordsman (despite Tadakuni showing no interest). He comes off as inexperienced and keeps protesting about the absurdities in the trio's RPG-world and storyline. Eventually, he tags behind Jack in his quest to defeat the demon lords.
In another adventure, Tadakuni is part of the Captain's crew as a rookie training to become the white knight. He appears just as clueless as last time, this time even forgetting the names of his teammates very easily.
Tadakuni hasn’t been shown to have any noteworthy abilities. Rather to the contrary, his general knowledge is shown to be poor relative to his friends. He is also exceptionally clumsy, having almost single-handedly destroyed lots of electrical equipment and having spilled paint all over the floor when trying to clean his classroom.
- Tadakuni’s last name remains unknown. He is the only member of the main trio whose full name hasn’t been revealed.
- With 38 appearances across 139 chapters (extras included), he is the 4th-most featured character behind Hidenori, Yoshitake and Motoharu. The amount of time he's seen for in the anime, however, is noticeably little in comparison.
- Despite being known as a neglected character, he secured the 3rd place in the character popularity poll (with 24,810 votes), beating out the other members of the main trio. Apart from this, there are other references to him in the poll:
- Tadakuni in girl’s clothing – 64th place
- Tadakuni’s sister’s brother – 64th place