Mr. Akashi is a minor villain from the Yu Yu Hakusho manga and anime. He was a teacher at Sarayashiki Junior High who disliked Yusuke Urameshi and tried to get Kuwabara expelled. He appears to be good friends with fellow teacher Mr. Iwamoto.
Mr. Akashi is a skinny man with brown hair, squinty brown eyes, and large bucked front teeth. Fitting to his behavior, Akashi vaguely resembles a rat. Like other teachers, he usually wears a suit and ties. Mr. Akashi is a cowardly and nasty man who makes as much trouble for Yusuke and his friends as he can, much like his comrade Mr. Iwamoto.
After Yusuke Urameshi dies attempting to save a child from getting run over by a car in episode/chapter 1, Mr. Akashi first appears when he and Mr. Iwamoto show up at Yusuke's wake to mock him. Both teachers are pleased with Yusuke's death, as it will help the school's reputation improve, and they joke that Yusuke probably saved the child by accident while trying to push him down and steal his lunch money. They are confronted by the school principal, Mr. Takanaka, who calls them disgraceful, insensitive, and idiotic. Both teachers leave the wake in anger.
In episode 3 (chapter 7 in the manga), Akashi punishes Kuwabara and his friends after they beat up a group of kids from a rival school after the group was harassing Keiko. Akashi tells them that if they cannot go one week without fighting, then they will get expelled from school and he will get Kuwabara's friend, Okubo, fired from his job.
As Okubo's mother is sick and cannot work, and his siblings are still little, this would leave Okubo's family with no money. Kuwabara and his friends reluctantly promise not to fight. As Kuwabara is walking home from school, Akashi follows him and the kids from before jump him (Akashi's anticipation for their arrival implies that he arranged for them to jump Kuwabara so that he would fight them and get expelled). Kuwabara is about to fight them, but ultimately exercises restraint and allows them to beat him up without fighting back.
This surprises and annoys Akashi, who tells Kuwabara's group the next day that in addition to not fighting, they must also each score a 50% or higher on their next test. With much studying (and more beatings) Kuwabara accomplishes this task. Akashi is frustrated, but he erases one of Kuwabara's answers at Mr. Iwamoto's suggestion and fails him (he plans out and does this scheme by himself in the manga). Kuwabara is surprised when he receives his test score because he knows for certain that he did indeed pass it.
When he notices the eraser mark on the test, he angrily aims to punch Akashi out but decides not to when he thinks about Okubo. Akashi laughs at Kuwabara as he walks away, but is confronted by Mr. Takanaka, who is aware that he and Mr. Iwamoto sabotaged Kuwabara's test, and angrily makes him fix the test and give Kuwabara the passing grade that he rightfully earned. Akashi is not seen again in the series, so it can be assumed that he was fired after this incident.