TV-Series
Description
Arihiko Inui is a classmate and the self-proclaimed best friend of Shiki Tohno. The two have known each other since middle school, having met during the time Shiki was living with the Arima family. Arihiko lives with his older sister, Ichiko, as their parents died in a disaster when he was young. The most traumatic event of his childhood was when the apartment complex he lived in collapsed. He was trapped in the rubble for three days and witnessed his grandmother die before his eyes, an experience that fundamentally altered his perception of death. He is a student at Metropolitan Souya High School.

Arihiko has a tendency to wander and has displayed an antisocial, delinquent attitude since elementary school. He enjoys living what he considers a renegade lifestyle, though he makes a point not to actively bother upright, normal people. He has a reputation as a womanizer, but his former girlfriends reportedly speak well of him, as he is the type of person who wants the girls he dates to be happy even after they have parted ways. Despite his callous and sometimes abrasive demeanor, he possesses a hidden supportive side, as demonstrated when he is the first to notice Shiki collapsing in class and helps him to the medical office. While he normally hates ghosts and monsters, he makes an exception for his friend Nanako, the spirit of the Seventh Holy Scripture.

The core of his character is his relationship with Shiki Tohno. The moment Arihiko first saw Shiki, he intuitively sensed that Shiki was broken and immediately declared him his rival, doing so while eating pudding he had just stolen from Shiki's lunch. He maintains a competitive attitude toward Shiki, such as wanting to get a girlfriend before him. Although Shiki sometimes wonders why he is friends with someone with such a weird personality, Arihiko’s loyalty during moments of crisis explains their enduring bond. Because of his own traumatic past, Arihiko does not react to death in the same way as a normal person, which allows him to coexist with Shiki without the fear or unease that others might feel.

Within the story, Arihiko serves a significant role in establishing Shiki's school life and providing early exposition. He is a grounding presence, representing the normal, everyday world from which Shiki is increasingly alienated. However, he is largely absent from the supernatural conflicts of the main narrative and does not appear in any of the original story's endings, nor is he featured prominently in certain routes. Additional background on his character is explored in the Kagetsu Tohya side story S.O.S. Nanako-chan, where he befriends the spirit he names Nanako.

Arihiko is a normal human with no supernatural combat abilities. His defining characteristic is his unique outlook on death, a direct result of his childhood trauma, which makes him an anomaly among ordinary people. He stands 174 cm tall and weighs 62 kg, with a birthday of October 24th and blood type B. He enjoys hobbies, gambling, and ramen, and dislikes plans that extend beyond three days and stupidity that affects those around him.
Cast