Kouta Otoyama

Kouta is an enigmatic character. He and Shipon develop a romantic relationship but there's still a lot about him that remains unknown. He has an older sister who runs an astronomical observatory in Japan. He often gives advice which is as enigmatic as himself.
He consistently achieves rank C in every class, without exception, regardless of how easy or hard the subject is. And when he was warned of the possibility of Ayaka attacking Shipon during training, he displays extraordinary piloting abilities beyond what his ship should have been capable of handling. Another example would be during a simulator-game where Rinna scored Rank A, Shima scored Rank B, he had scores Rank S. When Shima asks why Kouta does not do the best during class, especially since he is capable of it, he merely says: he wonders why also. Pierre once remarks "Talented hawks hide their talons" when referring to Kouta's skills.

(Source: Wikipedia)