Prof. Gareth
Played by Gareth
Personal Information
Full Name Gareth Nightman
Also Known As Prof. Gareth
Teacher Gareth
Status Deceased †
Relative(s) Jane Nightman † (wife)
Pepe (hinted step-son)
Love Interest(s) Jane Nightman (wife)
Physical Description
Gender Male
Hair Color Brown
Eye Color Blue
School Yandere High School
Species Human
Ghost (later)
Occupation Teacher (formerly)

Gareth is a supporting character and (former) antagonist in Yandere High School. He was Sam and Taurtis' teacher until he committed suicide in their former classroom, Room 23. (Episode 7)

Following his death, Gareth's spirit haunted both his house and the Yandere High School. While normally only appearing at night, he was sometimes visible during the day too, for example on school picture day (time 15:46 in Episode 37).

His grave was also situated behind the school, next to Salex's.


Gareth has short brown hair along with plain blue eyes. He seems to usually wear the boys' school uniform, even though he is the teacher, and has the default height.


Gareth was depressed following his wife Jane's disappearance, making comments about it in class. As the episodes progressed, Gareth became more and more depressed to the point of killing himself in his classroom. 

In Yandere, he is a little bit brighter than his older self and he is also a little bit nicer toward his students. However, when the children brings up his son's different race, Gareth was suddenly sad and ends class here.i

Though not necessarily a antagonist, he was kinda mean to Sam and Taurtis (specifically taurtis for joking about his wife. which started his fued against him.)

When Sam,Taurtis and Grian entered the school at dark, he would start haunting them and constantly accused taurtis of killing his wife and tried to make them lose their minds and commit suicide.

After Yuki was killed, he had a change of heart and thanked them for avenging his wife and admitted that taurtis wasn't the killer before ascending to heaven.

Love InterestsEdit

Jane is Gareth's wife. By the way he was affected after she disappeared, we can conclude that Gareth was truly in love with her, even though she was unfainthful. Unfortunately, Jane didn't really care about him and insulted him behind his back.


Gareth was close friends with Rowan and the two of them even watched movies at Rowan's. Rowan was also affected by his friend's death and was seen running away from the theater when Paul Blart made a bad joke about his friend's suicide. After Gareth's suicide, Rowan puts flowers on his grave.


Pepe is Gareth and Jane's "beautiful little frog son", but like it is pointed out by the students in Yandere) and the song Gareth makes them sing, it is hinted that Gareth isn't really his father by blood, but instead his step-father.


Gareth developed a grudge against Taurtis after the student jokingly brought up his teacher's dead wife. In the fourth episode of the Halloween special, after Salex told Taurtis that she always loved him, Gareth answered: "I didn't", confirming that he indeed hated him.