AraiBeni

AraiBeni is the het ship between Kobeni Higashiyama and Hirokazu Arai from the Chainsaw Man fandom.

Canon
Arai Hirokazu and Kobeni Higashiyama are Special Division 4's devil hunters. They both debut as they accompany Aki, who has just saved Denji from the Leech Devil. They are then assigned to Morino Hotel alongside Himeno, Aki, Power, and Denji to search for a devil reported at the location- kickstarting the Eternity Devil Arc. Upon being stuck on the 8th floor due to the eternity devil's power, Kobeni begins to panic about starvation and the possibility of death in the situation as Power laughs at her; Arai defends Kobeni by yelling at Power for laughing at his partners' distress before attempting to cheer Kobeni up by reminding her that she has to be strong to get her brother through college, which only escalates her current breakdown.

Kobeni later begins to grow more paranoid due to stress, suggesting that Power is the one keeping everybody on the 8th floor. Arai points out that Power is the blood fiend, and how her accusation doesn't make any sense. Upon him defending Power, Kobeni then accuses Arai of being a spy for the devils- to which she then threatens him with a knife. This confrontation then results in the Eternity Devil growing in size. Arai and Kobeni later both agree that Denji must die in order for them to escape the hotel. With Arai holding Denji down and Kobeni attempting to impale him with her knife, but she ends up stabbing Aki instead by accident.

After three days of Denji fighting the Eternity Devil, all assigned to the mission exit the hotel. Himeno goes with Aki, Denji, and Power to the hospital as she assigns the both of them to go back to headquarters and make a report of the event. During the shooting orchestrated by Katana Man and Sawatari, Arai is shot by one of the shooters, an elderly man, in the neck in broad daylight. In his final moments, he sacrifices himself and uses his body to shield Kobeni from the second bullet, shooting him in the head, killing him. Arai's death is seemingly a motivator for Kobeni going "berserk" and killing the aforementioned shooter and almost murdering Katana Man, as well as ambushing Sawatari. This is due to the fact that she thinks about her now deceased partner before, and after attacking the two of them, seeing flashes of his dead body. Arai's sacrifice also prevents Katana Man and his partner from obtaining Denji's chainsaw heart, saving him; As Kobeni's attack made the two flee the scene.

Fanon
The ship is popular in the Japanese part of the fanbase, it is however less popular than it's successor Galgabeni. AraiBeni and Galgabeni are often associated with the other because of the theory that the Violence Fiend is Arai. It's believed that Galgabeni roots from (possible) AraiBeni, as Arai was consistently attentive to Kobeni and ended up dying for her- which is very similar to Galgali's care for her. This roots from speculation based on the fact that Galgali says himself that the body he claimed had a fresh brain, and since Arai thought of Kobeni's safety in his final moments, Galgali's affection for Kobeni may root from remnants of memories he has from Arai's brain. The theory was further popularized after the release of Chainsaw Man chapter 65, in which Galgalis face is finally shown- fans of the ship were then very quick to point out the resemblance between Arai and The Violence Fiend.