She is voiced by Mary Elizabeth McGlynn.
As a young girl around the age of nine, Mei had to endure Kirigakure's brutal academy graduation ritual.
In the anime, shortly after Yagura's passing and Mei's ascension as the Fifth Mizukage, the village received an invitation from Konohagakure and Sunagakure to join an impromptu Chūnin Exams they would be hosting together. As the village was still recovering from the Fourth's passing as noted by Ao, it was decided the Kiri-nin would not take part in this event.
Mei is generally a kind and cheerful person, speaking well of others and attempting to avoid conflict. Mei proved to be more open-minded than the other Kage, as she had shown respect and was willing to listen to Gaara, at one point even defending him from the Tsuchikage's disrespectful behaviour, and later showing admiration for Gaara after seeing how pure-hearted he was. Mei also can be very flirtatious, as she remarked to Sasuke Uchiha that he was good looking, and expressed regret that she must kill someone so handsome, but would give him a kiss before that. She is also shown to be quite respectful to others despite her status as a Kage. She often ends her sentences with "kudasai", which translates roughly to "please" and refers to all her fellow Kage with the suffic "-sama", which translates to "Lord" ("Lady" if the person is female). She also stated to Madara that though she liked when men complimented her, she would hold off in his case.
Mei seems to be somewhat sensitive when it comes to her love life, as shown when she misheard Ao say that she was "past marriageable age", and threatened to kill him for such an "insult". This seems to be a running gag, as she has made similar mistakes on multiple occasions. She also has low tolerance towards insults about her age and appearance, as she was instantly angered when Karin called her an "old hag", and beat up Ao while Fū Yamanaka possessed his body and insulted her. Despite this, she is also very sharp-witted as she pretended to be able to undo Ao's barrier technique protecting his Byakugan to fool Fū into exposing himself possessing Ao's body.
Befitting her role as the village's leader, Mei cares about the welfare and history of Kirigakure. Under the belief that Yagura, her predecessor, had been manipulated by Tobi using genjutsu, she was prepared to fight Danzō Shimura, who also possessed a Sharingan which could cast a similar genjutsu. Though Mei is courageous and calm in battle, she is not above realising her or any one else's limitations as seen from her open acknowledgement that it seems as though Madara could not be stopped. Despite usually being quite fearless and determined in battle, she possesses a pessimistic outlook against stronger opponents as witnessed during her battle with Madara; though she felt they were fighting a losing battle and voiced the fact that their efforts seemed futile, this did not ultimately prevent her from fighting alongside her comrades.
Mei does care a lot about her marital status as well as her fellow Kage. In her Infinite Tsukuyomi dream, she dreamt she was married with the other four Kage celebrating it with her. She is also a person of honour as when Sasuke broke a wall and risked leaking her acidic Boil Release to the other Kage, she changed the pH to avoid harming them.