|Previous Affiliation||Thirteen Party, Plus Six|
|Abnormality||Superhuman Body Temperature|
|Manga Debut||Volume 6, Chapter 44|
|Anime Debut||Episode 20|
|Japanese Voice||Kenji Sugimura|
|English Voice||Blake Shepard|
Yamami Tsurumisaki (鶴御崎 山海, Tsurumisaki Yamami) is a junior of Class 13 and a former member of the Flask Plan's Plus Six. His project name is Star Master (占領役者, Sutā Masutā).
Tsurumisaki hates being around Normals and even compares them to garbage, a sentiment shared by his fellow member of the Plus Six, Shoko Kamimine. Like the rest of the Plus Six, he adds "Let's try and get along." after his introduction. Like the other members of the Plus Six, he is considered a basis for Class -13, having a personality that separated him even from other Abnormals.
Tsurumisaki has combed, light green hair (blonde in the anime), and the left side of his face is gray in color. He wears formal gray clothing (light brown in the anime) with a green tie (black in the anime).
Thirteen Party Arc
The group first appear before Youka Naze and Itami Koga after they kidnap Medaka Kurokami, offering to slow down the Student Council while Oudo Miyakonojou brainwashes her. Afterwards, the group rides the elevator to the first floor. Tsurumisaki introduces himself along with the others. After the Student Council head to the stairs, Tsurumisaki agrees with Otome Yunomae's suggestion to follow after defeating the Loser Team. The Plus Six are engaged by the Loser Team so that the Student Council can head down to the lower floors. After Kamimine protects the Plus Six, Tsurumisaki in turn protects her from Myouga Unzen, catching her weapons and melting them with his fingers. He remarks that if she wants to bowl, he will go with her, though his average is under seventy. He is himself protect by Yunomae. While Medaka and company prepare to descend to the thirteenth floor, Tsurumisaki and the others are still fighting the Loser Team. Tsurumisaki continues to fight Myouga. Later, he, along with the rest of the Plus Six and the Loser Team, is defeated by Misogi Kumagawa.
Kumagawa Incident Arc
Following the battle, Tsurumisaki is sent to the hospital along with the rest of Kumagawa's victims. Instead of external wounds, those who got pierced through with the giant screws took severe mental damage. On August twenty-second, Tsurumisaki is among Medaka's former enemies who show up to cheer for her during the President's Battle. He cheers for Medaka with her victory.
Kurokami Medaka's Successor Arc
Bouquet Toss To The Future Arc
Superhuman Physiology: Tsurumisaki is one of the only members of the Flask Plan who can use the elevator in Hakoniwa Academy's underground facility, along with Myouri Unzen and the other members of the Plus Six. He also claims to be a very poor bowler.
Superhuman Body Temperature: Tsurumisaki's Abnormality has not yet been fully identified, but he seems to be able to capable of melting metal with his fingers.
- When translated from kanji, Star Master means The One Servant of the Divine Leader.
- In the anime's opening sequence, the left side of Tsurumisaki's face is colored the same as the rest of his face; skin-colored instead of gray. The line running down the side of his face however remains unchanged.