|Strength||Incapable of self-defense|
Mei Mio wears the default female school uniform, unless customized by the player.
Before the February 8th, 2016 Update, she had cobalt blue colored hair worn in three pigtails: one on each side and one in the back. She also had bangs in the same style as the default Yandere-chan. Her eyes were cobalt blue as well. Her bust size is 1.4.
As of the February 8th, 2016 Update, she has cobalt blue hair pulled in a ponytail with wisps of hair that hang to the right. Her eyes are dark blue.
Among the personas currently implemented in the game, she is a Social Butterfly. She will happily pose for a picture if the player has their camera out. If she sees a corpse or witnesses a murder, she will run to the nearest crowd and call the police. She cannot participate in physical fights against murderers.
At 7:05 AM each day, Mei enters the school ground, fifth in line on the left to school, if facing the school gates. She will walk to her locker at 7:10 AM. At 7:15 AM, she walks into the plaza, on the left side of the fountain, and gossips.
Mei walks to class again at 1:30 PM and finishes her afternoon classes at 3:30 PM. From 3:40 PM to 5:30 PM, she eats octopus-shaped hot dogs with Kokona Haruka in the Cooking Club. At 5:35 PM, she walks to her locker and stands there before leaving the school building at 5:45 PM.
- Her name is a reference to the most popular female Japanese name in 2012, 7th most popular being Mei, 8th most popular being Mio.
- In older versions of the game, Mei's name was Tsumu Kotobu. The placeholder name was inspired by K-ON.
- Her male counterpart is Ryusei Koki.
- YandereDev has never liked Mei's iconic triple pigtail look. He finds them absolutely ridiculous and only used them because he had no alternative.