After the death of his parents in a car accident, Tatsuya tries to live to fulfill his father's last wish of becoming a "high caliber" man. After "saving" Seine from bullying, he insisted on trying to help her even after finding out the real goal of Seine. He is kind, optimistic and believes in other people's good side which is sometimes an obstacle in Seine's revenge. He is a bad cook, but Seine somehow is not bothered by his food. He has a crush on Seine and wants to be acknowledged as a "high caliber" man by her.
AiON
Tatsuya Tsugawa has just lost both of his parents in a car accident. While trying to live up to his father's dying wish of becoming an upstanding man, Tatsuya rushes to help Seine--his bizarre classmate--from bullies. Little does he know he is about to find himself in the middle of a supernatural war between the immortal Seine and sea creatures that can control humans. So much for being Mr. Nice Guy!
