An old friend of Tohru, he is a male dragon with a strong distrust for humans which leads to him questioning much of Tohru's actions and ideals in his earlier appearances. He shares some resemblance to the traits of his namesake, such as his cold demeanour and disdainful mentality. He appears as a refined young man with long black hair and red eyes in his human form.

Spoiler

After Tohru's attempts to find a place to stay for him (under the name Takeshi Ooyama), Fafnir eventually comes to live with Takiya, becoming obsessed with video games and popular culture.

(Source: Wikipedia)