Yuu Kannagi is the canonical Protagonist in God Eater, Burst and God Eater Resurrection. He is the main protagonist in God Eater 2: Undercover and God Eater: Knockin' on Heaven's Door, while he is a deuteragonist in several media adaptions, and a minor character in God Eater: -the 2nd break-.
Yuu is canonically the first game's protagonist (except in both the anime adaptation and The Spiral Fate). After the events of Resurrection, he and the rest of the 1st Unit become members of Cradle. He is absent during the events of God Eater 2 (and its expansion Rage Burst) due to being on a mission at the time. He later makes his physical debut in the games during God Eater Resonant Ops.
Knockin' on Heaven's Door
The Summer Wars
Yuu and Alisa are dispatched to Aegis Island on a protection mission to discover the reason for the Oracle Cell increase in the area along with Kanon and Gina (the latter of whom gets sent home early). During their mission, romantic feelings between the two begin to surface and results in both becoming closer to each other.
The 2nd Break
During The 2nd Break, it's revealed that Yuu had been sent on a mission out on the frontlines together with Lindow and Tsubaki. Alisa states many times her disappointment that he will be gone a while and often longs to see him again. She later receives a call from Yuu where the two proceed to talk to each other about their respective current situations, but is later cut short due to radio signal being weak. Later on, Kota arrives at Alisa's location and reveals that he had received a present from Yuu to be given to her where it's revealed to be the very same hat that Alisa wears throughout God Eater 2 and later on during God Eater: Resonant Ops.
As can be taken from the actions of the Protagonist from the original game and Yuu's own appearances in the light novel and manga spin-offs of the series, he is shown to be a kind and dependable young man who values the life of his comrades and can be somewhat reckless at times. He has a teasing side to his character as seen when he lightly makes fun of Alisa in both The Summer Wars and during The 2nd Break.
Yuu is a teenage boy with a light brown short hair (blonde in The Summer Wars) and turquoise eyes. He wears a blue Fenrir formal uniform with a white shirt under the jacket, a black glove in his left hand, black pants with two pockets, and short dark gray boots.
In the first and second chapters of God Eater: The Summer Wars, Yuu is shirtless and only wearing white swimming trunks. In the 3rd chapter, he is seen wearing a hooded jacket.
God Eater Resonant Ops
Yuu's appearance has undergone some minor changes. He still wears the same formal uniform pants but instead of a white shirt and blue jacket, he now wears a blue shirt underneath a white Cradle coat that is similar to Soma's.
- Kota Fujiki - His close friend and team member. The two were classmates from the beginning and developed a quick friendship even if Kota's actions causes him trouble at times.
- Soma Schicksal - While he proves to be gruff towards Yuu at first, he does gain a respect for Yuu after he proves his worth as the leader of the 1st Unit. Eventually, they end up on good terms, and he thanks Yuu in his final mail to him for the chance to repay Lindow.
- Lindow Amamiya - Lindow was the leader of the 1st Unit until he went missing during the Moon in the Welkin mission. Shortly after his disappearance, Yuu takes on his role leader. After he returns back to the Den, he formally decides to hand over his position as leader over to Yuu. Yuu sees Lindow as a dependable guy.
- Alisa Illinichina Amiella - Alisa values Yuu's life highly after he helped her recover from the incident that led to Lindow's supposed death. She admires him as a leader and is shown to have strong romantic feelings for him. Yuu seems to reciprocate to some degree as shown during The Summer Wars where the two end up falling asleep next to each other while holding hands. Yuu was also the person who gave Alisa her hat that she wears throughout God Eater 2 and later Resonant Ops.
- Sakuya Tachibana - Sakuya is the sub-leader of the 1st Unit and a dependable senior member. Before heading for Aegis island she informs Yuu (should you choose to visit her room shortly after they discover what Lindow's mission was) about her goals. Going from Sakuya's interactions with the Protagonist in God Eater, it can be assumed that they are on friendly terms. After Lindow was returned to duty by Yuu's actions, she thanks Yuu wholeheartedly, owing to a depth of gratitude towards him.
- Shio - Yuu saw Shio as a close friend during his interactions with her in-game.
- Licca Kusunoki - Due to him saving her from death by a Vajratail in-game, It is assumed that the two are close friends as well.
- Ren - He approached Yuu after he touched Lindow's old God Arc, with the desire to tell Yuu that he must be the one to kill Lindow. Ultimately, the plan was a cover for his real intention -- for Yuu to save his partner and return him to the Far East Branch. He then helps Yuu fight his way towards Lindow's sub-consciousness, asking him to give Lindow the will to fight again as they arrive. In the end, he sacrificed himself for them just so Lindow can return back safely. He thanks Yuu and Lindow before disappearing, content that his partner can see another day.
- When deciding to import a save file from God Eater Burst into God Eater 2, the database entry for the Protagonist will mention the name of the character that the player previously created. However, when declining to do so, Yuu's name will instead appear which makes him officially canon to the game's storyline.
- In God Eater: Knockin' on Heaven's Door, Yuu's name in English is written as "you".
- Yuu's character design is based on the artwork of the male Protagonist (God Eater).
- In Japanese, Yuu means "gentleness or superiority".
- His Japanese default voice in God Eater Burst and God Eater Resurrection is Takeshi Mori. In Pachi-Slot God Eater, however, his official Japanese voice actor is Shunzou Miyasaka, who is also Hiro Kamui's default voice.
- Yuu's first name is derived from the series producer Yusuke Tomizawa.
- "Yuu" is a play on the word "You," because he is/represents the player.
- Yuu's God Arc varies depending on what medium is being used to show him. In the light novel and manga adaptations, he uses the Clemencor set. In other appearances such as Pachi-Slot God Eater and God Eater Resonant Ops, he uses the default God Arc set that players starts with during the first game.