- "If you wish for glory... be strong!"
- — Sirius —
Sirius is a dark-skinned and powerfully built man. His most striking feature is that in place of a normal human head, he has the head of a jackal instead; he also has a tail, only adding to his canine features. His upper body is mostly naked and decorated with wave tattoos, but he has a small amount of clothing on his left shoulder and arm. He wears loose breeches on his lower body topped off with cloth shoes. As is usual with his class he fights with his fists, which are decorated with tight gloves.
As the Emperor of the Holy Palace, Sirius prides himself on his strength and his place in Icolo. Very arrogant, he has the tendency to look down on people weaker than him. His personal belief is that only those who have fought their way to the top and destroyed all opposition are worthy of respect. He is very close with Alkaid, despite the fact that he almost always argues with her whenever they meet.
Offline, Sirius is a Korean working in Japan.
Sirius is very proud of his position within Icolo, and was offended when Antares allowed a non-member like Haseo into Icolo's @Home. However, once Haseo becomes Emperor of the Demon Palace by defeating Endrance, Sirius grudgingly accepted him as a person worthy of respect.During the AIDA Server Incident Sirius became infected by the AIDA that stole Atoli's Epitaph Innis. Helen preyed upon his fear of losing his title and caused him to become increasingly violent, even towards his friends. Additionally the AIDA used Innis' Mirage ability to created immortal duplicates of Azure Balmung and Azure Orca that Sirius could use as team mates. Disturbed by his behavior Alkaid enlisted Haseo's help, hoping that together they could help bring back the Sirius she had known. The two entered the Holy Palace Tournament together hoping to fight against Sirius, but unfortunately only Haseo made it to the final match, Alkaid having fallen into a coma after being PKed by Bordeaux. Alongside Kuhn and Endrance Haseo fought against Sirius and his companions in a fierce battle. When the battle began to turn in Haseo's favor Sirius unleashed his AIDA in a final desperate attack. In turn Haseo released Skeith which destroyed the AIDA possessing Sirius.
Initially Sirius was angry over his loss, and the loss of his AIDA. Claiming that Haseo had "stolen his power". However after learning that the same power he'd been using had also put Alkaid into a coma Sirius realized the evil of his actions and was consumed by guilt. Later, Sirius approached Haseo during his coronation as Holy Palace Emperor, he told him that even though he'd learned his lesson, he would never be able to forgive himself for what had happened to Alkaid.
During Sakaki's PK tournament, Sirius emails Haseo to save Taihaku so he didn't become like himself and Endrance, and eventually tries to defeat the Hetero Trio, remarking that they're hacked PCs. He's defeated, unfortunately, and becomes a Lost One. Later, after AIDA is defeated, he helps Haseo fend off Cubia's Gomoras at the Arche Koeln Waterfall, fighting alongside Alkaid, Taihaku, and several arena rankers.
- Sirius's Japanese voice actor, Isshin Chiba, also does the voice of Silver Knight.
- Sirius's name in the Japanese version of the game was Tenrou, the traditional Sino-Japanese name for the binary star Sirius. This was officially romanized as Tenrow in most materials however, possibly to be unique.
- Interestingly enough, Sirius has his own even more flashy version of Divine Awakening, which is used in the Arena Battle in Vol 2. The name of his awakening is Demise Claw.
- Sirius's PC is 7'6" (231 cm) in height, making him the tallest G.U. character by less than an inch.
- Sirius is also often called the "dog star," which may be related to the jackal-like head of the character, in addition he is also called the "Azure Wolf."
- Sirius' weapon is a level 67 gauntlet called Death Fist equipped with quick rengeki and critical +10%.
- The Shopkeeper from .hack//LINK has a picture of Sirius in his collection.