Mai Nametsu (Japanese:
滑津 舞Nametsu Mai) is a second-year manager of Date Tech High's Boys' Volleyball Club.
Mai has big, round brown eyes with long eyelashes and thin eyebrows. Her hair is dirty blond and usually wore in a side ponytail to the left. She is usually seen wearing a Date Tech High tracksuit during the team's matches.
Mai is generally very outgoing and cheerful. She is very supportive of her team and won't hesitate to praise them for a good play. She also has a good sense of humor. This is shown when she says "Nice catch" to Coach Oiwake when he caught a ball after his team messed up during a match.
Mai appears to have a more blunt side to her personality. She is seen slightly disapproving of the overzealous third years when they constantly show up to spectate the team's matches. In addition, she, along with Oiwake, is seen wearing a smug face toward Coach Ukai after her team shows off their immense improvements in their serves.
Not much is known about Mai's background, but she appears to be a rather experienced manager. She is familiar with her team's strength and knows what areas still need to be worked on just from watching their matches. This seems to imply that she has been the manager for a while now.
Spring High Preliminary ArcEdit
During the Spring Interhigh preliminaries, Mai watches the match between her team and Aobajōsai High together with Coach Oiwake. She is very supportive of her team and can be seen either doing a fist pump or outrightly praising the players when they make a good play.
Tokyo Nationals ArcEdit
During the practice match against Karasuno, Mai observes her team and takes note on their performance. She is delighted to find the team fired up and performing well in maintaining their blocks. Later when the retired third years comes to spectate the watch, Mai questions where they find all the free time due to them constantly showing up uninvited. Throughout the match, she pays close attention to the strength and weakness of her team. When Aone attempts his newly learned jump serve, she and Oiwake wear a smug expression while silently gloating over their team's improved strength to Ukai. Also she is quick to realize that the team still needs more work on receives after Karasuno's pinch servers easily scored on them. 
Mai works well with Coach Oiwake. The two are often in-sync in terms of their thoughts and actions when it comes to their team's performance. She also appears to have a good relationship with the players, as shown when she refers to Sakunami as "Saku-kun".
- "Good one...!! Nice receive, Saku-kun!!" (To Sakunami during the quarterfinals, Chapter 127)