Masafumi Usui

Masafumi Usui (笛吹 正文) was Kazuyoshi Usui's younger brother and the original source of the "Switch" nickname. The reason for his nickname was because he was called Usui-chii by his friends and it sounded like "Switch". Thus, it became his nickname.

Backstory
Masafumi is a year younger than his brother. He was brilliant with computers, and possessed a very scientific mind. He created the speech synthesis software that Switch always uses. Prior to his death, he had not perfected it. When Sawa sought help, Masafumi made suggestions. He was upset when Kazuyoshi would not accompany them to buy self-protection equipment. He was killed by Yukino, who mistakenly believed that he and Sawa were dating.

Appearance
Masafumi has black hair and black eyes. He also wears thick black glasses.

Personality
Masafumi is kind and supportive of Kazuyoshi and Sawa. When Kazuyoshi refuses to go with Sawa, Masafumi reminds Kazuyoshi of their childhood photo. He tells Kazuyoshi that he does not like how his older brother acted so cold towards Sawa and him.

Quotes

 * To Kazuyoshi: "I guess I've misjudged you..even though I'm always relying on you..I don't like you like this, An-chan."