Sect Ijuin

Sect Ijuin (伊集院セクト, Ijūin Sekuto) is a character from the Yu-Gi-Oh! 5D's manga. He was originally one of Yusei's closest friends from Satellite but is currently sided with Roman Goodwin under the guise of the Skeleton Knight after acquiring the "Duel Dragon", "Beelze, King of Dark Dragons".

Etymology
In Japanese, last names are said before first names, making him "Ijuin Sect", which contains the term "insect".

Voice/Mannerisms
In the Japanese version, Sect has an habit of saying "ari" ("ant" in Japanese). According to an omake from volume 1, this is because Sect once played an "ant" Deck, but changed it to a general Insect Deck because ants make weak enemies.

Appearance
Sect is quite small, having a similar height and appearance to Leo. Sect originally wore a white biker outfit with a blue pattern and a helmet of a similar design. He also wore a pair of goggles on his helmet and a crimson scarf. After siding with the Skeleton Knight, Sect wears dark medieval armor and a cape, similar to that worn by Haou. Sect also has brown hair and blue eyes. After Summoning "Beelze, King of Dark Dragons" his skin began to crack, leaving scars across his face. Sect's Duel Runner is in the shape of an ant, referencing his Insect Deck. Sometime after his Duel with Jack Atlas, Sect received a new, more modern Duel Runner with a sleek design.

Personality
Sect was originally a fun person, believing that duels were fun, even when he lost. After acquiring his "Duel Dragon", he became quite secretive, hiding it from Yusei. After being affected by it's Shadow Miasma, Sect's personality became dark with him believing that Yusei looks down on him rather than seeing him as a rival. During his duel with Akiza, Sect mocked her throughout the duel, especially when she wrongly predicted the turn he'd lose.

Biography
Sect challenges Yusei Fudo to a Turbo Duel, in a Satellite factory, in the hopes of defeating him. Yusei wins, but is impressed by Sect's performance and accepts Sect as his rival.

After the Duel, Sect climbs up on top of a tank and, following an urban legend, holds two cards up to the sunset. He clasps them together and prays that the Skeleton Knight will give him rare cards to use to beat Yusei. The Skeleton Knight appears, but refuses to give cards to someone this weak. He takes Sect captive and knocks him out. The knight challenges Yusei to a Duel in order to save Sect. During the Duel, Sect wakes-up and starts cheering for Yusei.

Yusei takes Sect on the back of his Duel Runner to bring him to the hospital. However, Yusei is forced into a Turbo Duel with Jack Atlas on the way. During the Duel, Sect falls off Yusei's Duel Runner. Yusei abandons the Duel to save him and both of them fall into a body of water.

Yusei manages to get Sect to Puzzle Hospital, where he is treated for a minor concussion.

While Sect is in the hospital, the Skeleton Knight appears to him in a dream. According to the ancient edicts, the knight says that he shall grant Sect's wish. Sect wakes up, frightened, but finds himself holding a card.

Sect arrived at the stadium of the D1 Grand Prix, wearing a poncho, shortly after Yusei started his Duel with Greiger. Sect urged Yusei to show everyone the outcome of his special training. Akiza Izinski approached Sect over this and asked if he was with Yusei. Sect was shy at first, wondering if Yusei knew this pretty lady. He acted tough and said that he is Yusei's rival. He was shocked when Akiza correctly guessed that Yusei's new training meant he had developed a new Sense.

During Yusei's Turbo Duel with Hunter Pace, Sect overhears some of Hunter's goons joking about them taking Yusei's turbo chip out of his Duel Runner so Hunter could win the race by overtaking Yusei. As this happened, Sect began to pick a fight with the goons and when they thought they were getting the upper hand, his "Beelze, King of Dark Dragons" began to infect him with pure darkness that gave him enough strength to defeat Hunter's three goons.

After this, he disappears without a trace. After hearing about these events, Yusei began to look for him throughout the city, as Sector Security were looking for him in order to place him under arrest. Lazar observed these events and informed Rex Goodwin that Sect has a shadow card. Overhearing their conversation, Jack Atlas walked out and began to look for Sect, claiming that he wanted his shadow card.

After these events, Sect rode to the harbour on his Duel Runner, trying to escape from all of the attention his fight had brought up, only to be cornered by Jack, who challenged him to a Turbo Duel. Suddenly, the shadow card began to infect Sect again, and both prepared for a Duel of darkness.

During the Duel, Yusei Fudo drives in between him and Jack, causing Sect to snap out of his dark manner for a short while. However, after summoning "Beelze", he begins to think that Yusei is looking down upon him and making fun of him because he was weak.

As the Duel progresses, Sect becomes more and more consumed by the shadow card, even to the extent of having his skin begin to flake off, showing that the shadow card carries some form of curse. During the Duel, Jack gains a massive upper hand by summoning his "Dark Highlander", but shortly after this happens, the Skeleton Knight appears and takes Sect with him, ending the Duel and leaving Jack and Yusei shocked at what just happened.

Later, as the second stage of the D1GP takes place, Sect Duels Akiza under the Skeleton Knight's orders.

Yusei Fudo
Sect originally saw Yusei as an older brother figure, occasionally calling him "aniki" (big brother in Japanese). He believes that Yusei is an awesome Duelist who deserves to win all. After Sect became an ally of the Skeleton Knight, his once friendly outlook on Yusei turned sour, as he now believes that Yusei looks down on him as a weak Duelist.

Skeleton Knight
When Sect wished for cards from the Skeleton Knight, his wish was granted and the Skeleton Knight gave him the poweful, dark card, "Beelze, King of Dark Dragons". But this power came at a hefty price: Sect's soul. It is due to this that Sect is now a member of the Skeleton Knight's Crusade, a dark and powerful organization consisting of several Duelists who wished for cards from the Skeleton Knight. All of them seek to destroy the Signers. Sect sees the Skeleton Knight as a powerful figure, maybe even father-like, as he rescued Sect from his Duel with Jack before he lost.

Insect/Hell Deck
Sect uses an Insect Deck. After siding with the Skeleton Knight, he begins to incorporate the "Hell" Archetype, also using several cards which reference "Death" such as "Fruit of the Dead". He also uses various methods to Swarm Synchro Material so he can Synchro Summon "Beelze, King of Dark Dragons" with ease through cards such as "Call of the Haunted" and "Hell Summon".

Ant Deck
An omake in volume 1 revealed Sect originally played an "Ant Deck". However, he later changed it to a general Insect Deck because ants make weak enemies. His ace monster was "Hammerhead Ant".