Kikuoka Seijirou

Kikuoka Seijirou (菊岡誠二郎), known as Chrysheight (クリスハイト) in «ALfheim Online» (ALO), is a supporting character in the Phantom Bullet Arc and Alicization Arc, as well as a reoccurring character throughout the Sword Art Online series. He allegedly works for the Ministry of Internal Affair's Telecommunications Bureau, Advanced Network Division, Second Office (the «Virtual Division») and, at some point after the end of the Sword Art Online incident, began playing ALfheim Online for research purposes. However, Seijirou is actually a Lieutenant Colonel of the Japan Ground Self Defense Force, who voluntarily transferred over to the Ministry of Internal Affair's Telecommunications Bureau for the sake of his plans on Project Alicization.

Background
Kikouka Seijirou was an investigator in the «Sword Art Online Case Victims Rescue Force», and the one who told Kazuto which hospital Asuna was in. Though he is stated to be part of the virtual division, Kazuto suspects he is part of the JSDF after tailing him. He takes advantage of Kazuto's gratitude by using him as an investigator for issues, and uses other people like watchdogs over the VR network.

Seijirou was also one of the original 1,000 beta testers for the original Sword Art Online. However he did not transfer over to the full version of Sword Art Online because he realized that the technology could be used for more than just military training programs and started working on Project Alicization.

Extra Edition


On July 25, 2025, Seijirou had the SAO Survivor School set up an emergency counseling session with Kazuto, to his surprise, in order to gather more information regarding the events of SAO, and its aftermath. The game's logs only displayed the locations of players at certain times and, with Kayaba Akihiko's death, Seijirou wanted to hear Kazuto's story. Kazuto, after informing Seijirou that he had to be somewhere later, agreed to tell him everything that happened: from the incidents in SAO, to Kirito's "victory" over Heathcliff, and then explained the situation after he discovered that Asuna, along with 300 other SAO players, was trapped by Sugou Nobuyuki, and how he came to locate her in ALfheim Online.

Seijirou was later seen calling Kazuto through his cellphone.

Phantom Bullet Arc
Kikuoka Seijirou made his first appearance at the beginning of the Phantom Bullet arc as an acquaintance of Kazuto, contacting him for advice concerning a troubling matter. On December 7, 2025, he introduced the Death Gun problem, trying to debate on how Death Gun could kill through the tamper-proof, safety-conscious AmuSphere. He and Kazuto reasoned that such a feat was impossible, but he convinced Kazuto to investigate for a sizable reward.

After Kirito entered the «Bullet of Bullets» on December 14 and encountered Death Gun after the death of Pale Rider, Asuna contacted Seijirou and got him to log in to ALfheim Online where she interrogated him to find out the true reason behind Kazuto converting his avatar to Gun Gale Online. He, after extreme pressure, revealed everything to Asuna.

In the resolution, he met with Kazuto and Asada Shino on December 16 for a debriefing of the incident and apologized for the danger. Kazuto also brought up the issue of the dangers that some aspects of VRMMO games pose, such as invisibility being a gateway to misbehavior.

Alicization Running
On July 5, 2026, it was revealed that he was a Lieutenant Colonel from the Japanese government's Self-Defence Force, and was in charge of Project Alicization. He oversaw its conception and formulation, directing the soul cloning of newborn babies and then the acceleration of the Underworld society.

It was also revealed that he had taken advantage of the «Gun Gale Online Incident» to form a relationship with Kazuto. His true goal was revealed to have been enlisting Kazuto's help for Project Alicization.

Gallery

 * See Kikuoka Seijirou/Image Gallery

Trivia

 * Seijirou is a man who likes talking about disgusting things. For example, he excitedly talked about the making of a Kiviak in great detail in a cafe.
 * Seijirou's character name, Chrysheight, which is formed from the English words «Chrysanthemum» and «Height», comes from Seijirou's family name, Kikuoka (菊岡), which is written using two kanji: Chrysanthemum (菊) and height (岡).
 * Chrysheight's skill as a mage in ALfheim Online is acknowledged by General Eugene.
 * In the web novel version, all of Seijirou's family members died when he was a baby in the 1980s due to an air traffic incident. According to Kirito's memory, one of the proposed causes for the incident was a fighter misfiring a missile.

Navigation
Seijirou Kikuoka Кикуока Сэйдзиро