|Age:||16 years old|
|First Appearance||Last Appearance|
|Chapter 0 (Prologue)|
Mai Mashiro life was tragic as told in the manga itself it's implied her Father was a child molester who molested either her younger sister or her and one day she massacred her entire family including her unnamed Father, Mother, and Sister.
Around an unknown period, she had met Tomohiro Machiya who was filming a dead bird and as he was teased by neighborhood boys (likely classmates as well.) She had gone over to him and started a conversation which led to him calling her beautiful.
Mai has short dark blue hair and is moderately curvy.
Mashiro Mai has a split personality, a psychopathic murderer and a naive schoolgirl in which the latter caused her popularity in DeadTube.
She is extremely manipulative, as seen where she manipulates Tomohiro Machiya to betray and kill his first love, the film club director.
Her sadistic nature may have spurred from her belief of beauty coming from things not normally associated with beauty. This was later the cause of her family's murder in an attempt to recreate 'beauty'.
On the other side, Mashiro displays the naivety of a schoolgirl, blushing when she is filmed by Machiya, even crying when her first kiss wasn't him.
Mai is a teenage girl in her high school swim club who approaches series protagonist and film club student Tomohiro Machiya and asks him to film her constantly for the next two days. Mai has him film her swimming, with friends after school, and even in compromising situations, such as in the shower or even going to the bathroom. Mai even has him film her all night while she is asleep. Along the way, Mai behaves seductively and strongly implies attraction to Tomohiro. Mai reveals a boy named Nozomu Yamamoto who bullied Tomohiro in middle school to be her boyfriend, however, he keeps filming as Mai goes on a date with her Yamamoto and even enters an abandoned factory and starts to have sex with him. Before the Yamamoto can complete the act, however, Mai seizes a metal pipe from the floor of the factory and brutally clubs him to death. Tomohiro is strangely transfixed by the scene and realized to his horror that he is aroused by the murder. Mai, still nude and covered in her victim's blood, asks Tomohiro to stand still and kisses him, before taking the memory card from his camera. When she kisses Tomohiro she reveals that she is still a virgin as Yamamoto never penetrated her.
Tomohiro meets Mai the next day at school, and she tells him that she has managed to frame an innocent man for her crime, and also declares herself to be Tomohiro's lover. She also pays him five million yen for his camerawork and tells him to continue working with her as a camera, this time to film the head of his film club, a girl named Oshima Sanagi for five days, claiming she will commit suicide after five days.
During a field trip attended by the entire film club, along with Mai, Tomohiro films them, until one day until Oshima's death. Throughout the field trip, Oshima seduces Tomohiro. On the last day of the drip, Oshima takes Tomohiro aside and states that she received a text and photos from Mai showing her boyfriend murdered, as well as three boys in the film club. Mai also states that she had Mizuno, a girl from the film club raped by three male accomplices. The text warns that if Oshima does not commit suicide in two days, more of her friends will die. Oshima and Tomohiro formulate a plan to ambush and kill Mai the next day on the roof of the school. Shortly before enacting her plan, Oshima confesses her love for Tomohiro and kisses him.
The next day, Mai visits the roof of the school, and sees Oshima about to commit suicide, but then shocks everyone by revealing she knows Tomohiro is hiding behind the door. At that moment, Mizuno tackles Mai to the ground and demands that Tomohiro kill Mai now, stated that she is behind her rape and the other boy's murder. Mai, however, managed to recover and tosses Mizuno at Oshima, pushing Oshima off the building. Tomohiro attacks Mai with a baseball bat and clubs her to death. Moments later, however, Oshima appears from the stairs, perfectly alive, and states she landed on a soft awning set up a floor below, and the dead body on the ground was actually a girl she and two accomplices had kidnapped and thrown from the window. At the same time, the two male accomplices reveal themselves, and Mizuno reveals she was an Oshima's accomplice as well. Oshima states that Mizuno killed a random person, who was not really her boyfriend, and even, more bizarrely, Mizuno allowed herself to be raped by three boys in the film club, who were in on the scheme and was later murdered by Oshima. Oshima then reveals her true "love" was not a person at all, but her obsession with producing amateur snuff films and uploading them to a site called "Dead Tube". She also reveals her interest in Tomohiro is a lie, and that she is sexually involved with both of her male accomplices. She then asks for Tomohiro's last words.
Tomohiro responds "Too bad", and Mai apparently rises from the dead, drawing an awl and a collapsing baton, and brutally murders all of Oshima's accomplices. Oshima picks up Tomohiro's baseball bat, and attempts to defend herself, only to discover it was actually a foam bat covered in bandages filled with fake blood- Mai faked her own murder. Mai hits the bat hard enough to break it with her baton. Oshima desperately undresses and offers Tomohiro sex in exchange for his life. Mai tells her she will spare her life if she kneels before Tomohiro and licks his boots. Mai quickly reveals she is lying, that she and Tomohiro had planned all of this and seizes Oshima and hangs her by the ankles from the school building and cuts the rope, causing her to fall to her death. The film is then presumably uploaded to "Dead Tube".
- She refers to herself as perverted but not kinky because of the fact that she is a virgin.
- Its considered she was the first Deadtuber for slaughtering her family.