Sugou Nobuyuki

Sugou Nobuyuki is the director of the research institute of Recto Progress Inc. He was Fairy King Oberon (妖精王オベイロン), the main antagonist of the Fairy Dance Arc. He is also Asuna's ex-fiance.

Background
Originally selected by Asuna's father to marry Asuna, he was adopted into her family on her father's wishes. He attended the same school as Kayaba Akihiko, who he viewed as a rival. During the « Sword Art Online » incident he took advantage of the chaos to steal test subjects for research along with Asuna. In «ALfheim Online » he adopts the persona Fairy King Oberon.

Fairy Dance
As the Fairy King Oberion, he keeps Asuna locked up in a bird cage at the top of the World Tree. In the real world, he confronts the powerless Kazuto by voicing his intentions of wedding the unconscious Asuna. While keeping Asuna locked up in ALO, he constantly visited her just to fool around with her. From his actions, one could say that he is a pervert. After Kirito manages to ascend the World Tree, Oberion and Kirito have a devastating fight. By using his system commands, Oberion is able to completely dominate Kirito. Fortunately, Kayaba Akihiko saves Kirito by overriding Oberion's authority. Then, in the real world, Sugou attempts to kill Kirito when he is running to Asuna's hospital. This backfired and ended up with him going to prison.

Light novel Notes

 * Sugou did NOT commit neotare upon Asuna's unconcious body in the real world as stated in the light novel he stated himself: "After taking the purity of your heart here, I'll take the purity of your body there!! So fun, a truly unique experience!!". This implies that Asuna's body had been untouched until later on in the series.
 * Sugou only commits immoral acts upon Asuna's body in ALfheim and none of them involve any more than licking or caressing her cheeks.