Hideki Sohta is the former teacher of Aki's class. He was born December 6th, 1986. He is known by his students to be a "kind and caring" teacher, when in reality this is false. He is described as a suave and handsome man. He seems to have a hand fetish as well. Sohta wears a suit as his work uniform and parts his sand colored hair. While he was still attending high school, Sohta was considered unattractive and was bullied for it in school. He is referred to as Kurata instead of Sohta in Misao: Definitive Edition.
Before the Curse
The first we see of Sohta is him scolding Aki after she's caught daydreaming and staring out the window instead of paying attention in class. After his reprimanding, he goes back to teaching the class and Aki's classmates giggle at her for getting in trouble.
The Curse Begins
Like the others, Sohta was mysteriously transported to another location when Misao enacted her curse. It turns out that he was unfortunately teleported to the Class 2-A locker, which was locked from the outside and effectively trapping him there until the player finds him and lets him out. Once free, Sohta will head to the Infirmary and can be found there with Ayaka after.
Finding Misao's Dismembered Parts
When the player comes to the Infirmary, Sohta can be found tending to a distressed and traumatized Ayaka. He will say that Ayaka had been attacked by a monster and asks Aki to go to the Staff Room to find a tranquilizer. Unfortunately, upon Aki's return, she finds Ayaka dead on the floor and Sohta wounded, to which he tells the player that it was the monster yet again, but he couldn't save her. Shortly after, Sohta gives Misao's arms to Aki.
Ending
Once Aki finds all of Misao's body parts, he/she learns from Onigawara that one more person must be killed in order to end the curse; either Sohta or Tohma must die. Should the player decide to kill Sohta, Aki will bash him with the bat, leading to the good ending of the game, otherwise sparing him leads to the bad end.
After making the final sacrifice and offering Misao's body parts, thus breaking the curse, Aki learns from a flashback that Sohta appeared to comfort Misao after being bullied by Yoshino. This, however, directly contradicts an earlier statement he said to Aki, in which he had said he didn't have time to listen to Misao and had ignored her. Misao tells him that she'd had her heart broken and that she was crying to herself in the corner of the bathroom. The older man replies that he himself had been like that once, but Misao had found that hard to believe, complimenting on his gentle and popular nature. After comparing his own past to her, but remarking that she was much more 'charming', Sohta then hugs her from behind and starts touching her hands, causing her to become confused and uncomfortable. In response, Misao pushes him away and backs herself into a corner, but Sohta continues to pursue her as the scene fades. It is assumed that Sohta rapes her. Off screen, Misao screams and the teacher yells back, outraged at Misao's rejection. When the screen comes back, Misao is dead, with Mr. Sohta standing over her body. He then drags her dead body into the bathroom and holds out a saw, dismembering her body.
If Tohma is killed instead, Sohta is released from the curse and discovers that Aki learned the truth. Aki begs to not be killed and tries to run, only for Sohta to catch up to him/her and the screen fades black; he presumably kills Aki to silence him/her. In the next scene, Sohta is seen comforting a girl named Miho who got into a fight with her friend and offers to take her home, which she agrees.
Sohta's Grave
If you touch Sohta's grave in Truth mode, you'll first find yourself in Sohta's room. You'll learn on the computer that he was happy to be loved by all, but it was actually a "mask" he wore that everyone loved. Afterwards, you'll see he apparently hates that "everyone goes on" about his appearance. In a flashback of his featuring Ayaka and some of her friends, Sohta eavesdrops on them and hears them go on about how great-looking he is. He walks away, frustrated, but after he leaves, Ayaka's classmate says that Sohta is kind and reliable, and his biggest charm is that he is not all appearance.
Back at Sohta's house, it is revealed that Sohta was considered unattractive in his high school years. He used to get bullied because of his appearance. Every time he made contact with something, the others refused to touch it afterwards, even if they owned it.
We learn that later on, he took a wounded cat to a veterinarian who told him it couldn't be saved, so Sohta dug a tomb for this cat.
He used to have a friend at that time named Takano. He had a crush on her, and she didn't mind being teased about being around Sohta. They met daily but didn't talk a lot, and they were happy that way. However, when he confessed his love for her, she refused harshly before apologizing. Takano didn't want to get that close to Sohta, but was feeling pity towards him. She told him they should stop meeting. Sohta was angry. The sprite action leaves some doubt, either Sohta was trying to kill Takano, or was going to rape her. He was then stopped by a teacher.
Aki then follows Sohta deeper into the house, where he is slashing a dead body (it is unclear whose it is) while lamenting about how no one accepted him as an adolescent. Things turned around when he "changed his face"; everyone loved him, but Sohta says that everyone only loved him for only his face. Aki then comforts him, saying that all his students love their kind and reliable teacher, and that she loves him for who he is and what he is now. Sohta is surprised, and Aki gives him a hug. After this, Aki is transported back to the other world, where the others' graves are.
He doesn't reincarnate, but the cat he couldn't save does. Aki remarks, "This kitty was happy being cared for in its last moments..." Another theory was that he was reincarnated into the cat he had loved.
Ayaka's Hairpin
In Truth, touching Ayaka's Hairpin next to Sohta's grave reveals how Ayaka really died. While she was rummaging through Sohta's love letters in his desk, she discovered Misao's arms. Sohta then catches her in the act and chases her to the infirmary. However, before he can silence her, Aki walks in; Sohta claims that Ayaka was attacked by a monster and convinces him/her to get a tranquilizer from his desk. This gave him enough time to murder Ayaka in cold blood, then inflict a self-injury to make it look like they were attacked by a monster.
