Kotoha Kutsugi

Kotoha is the best member of the Covert Squad and uses shurikens as her weapon of choice. She views Kuon with great suspicion and as a threat when her identity is revealed, but later comes to accept her as her leader once again. She is said to never smile, but did towards Kuon at the end of episode 16. Kotoha is also a master of unarmed combat and disguise, posing as the caretaker of Gokujou-ryou in episode 11 during a soccer match between the Gokujou Seitokai and the student council of another school. The game was later won almost single-handedly by her, despite the other team possessing a huge lead in the earlier parts of the match.

(Source: Wikipedia)