TV-Series
Description
Jinpachi Arashiyama is one of the supporting characters in the anime series Nanaka 6/17. He is portrayed as a delinquent and serves as the rival of the main character Nenji Nagihara. Jinpachi is the older brother of Satsuki Arashiyama. He is also identified as the heir to the Arashiyama family dojo.

In terms of his personality, Jinpachi frequently engages in fights with his rival, Nenji, but he always loses these encounters. He becomes irritated when Nenji begins to act more maturely, as this behavior change disrupts their usual dynamic. Despite his tough exterior, Jinpachi is shown to have a softer side, particularly when he encounters Nanaka Kirisato. He is charmed by her childlike attitude and innocence, which develops into a romantic infatuation with her.

Jinpachi's role in the story is primarily as a comedic rival and a secondary love interest. A key event that defines his character occurs in the third episode. After losing a fight to Nenji, Jinpachi is forced to get his hair cut in a style identical to his rival's. Shortly after, Nanaka's glasses are broken, and due to her poor eyesight, she mistakes Jinpachi for Nenji. He agrees to accompany her on errands, which turns into an outing resembling a date with a young child. It is during this time spent with a six-year-old-minded Nanaka that he falls in love with her.

His most significant relationships are with his rival, his sister, and his love interest. His rivalry with Nenji Nagihara is central to his character, defined by a cycle of losing fights and feeling frustrated by Nenji's personal growth. His relationship with his younger sister, Satsuki Arashiyama, is complex. Satsuki is displeased with his lack of seriousness regarding his duty as heir to their family's dojo, and she often punishes him with surprise attacks to whip him into shape. His infatuation with Nanaka Kirisato is his primary motivation for much of his screen time, as he becomes determined to protect her and be worthy of her affection. This is encouraged by his sister, who decides that she wants Nanaka to be her "big sister" and insists Jinpachi improve himself to be a suitable match.

Jinpachi does not undergo a dramatic, world-changing development, but his character arc involves a shift in focus from being a simple delinquent rival to being a young man motivated by his feelings for Nanaka. His sister's constant discipline and his desire to be worthy of Nanaka push him toward a less chaotic path.

Regarding abilities, Jinpachi is depicted as a capable fighter, but his specific skill set is defined more by his consistent failures in combat. He regularly loses in his fights against Nenji and is also frequently overpowered and corrected by his younger sister, Satsuki. His most notable ability is perhaps an ironic lack of success in the very field he pursues, which serves as the primary source of his comedic struggles.