This page will be updated when the arcs advance, but now it will only contain general information and his character progress following arc 2.
Information:
Kazuki Tanaka is the main protagonist of Re:ZERO - Starting Life in Another World: Co-op Route.He is a former loner who was mysteriously transported to the Al Mathers Territory, where he was granted the Authority referred to by Subaru as "Return by Death."
Appearance:
Kazuki is a young man in his late teens, standing at 178 cm with an average build — neither muscular nor thin. He maintains a balanced physique both before and during his stay at the Al Mathers Estate.
He inherited most of his features from his father, including hair and eye color, but his eye shape and softer expressions come from his mother.Kazuki has jet-black hair and round obsidian eyes that resemble the night sky, contrasting with his younger sister's bright blue eyes, inherited from their mother.
His naturally handsome features were once dulled by exhaustion and sleeplessness, but became more defined after recovering from the Ulgarm incident. Were it not for his solitary nature, his looks could easily have drawn the attention of many girls.
Personality:
Kazuki is an introvert who avoided forming close relationships during high school, dedicating himself entirely to his studies in hopes of becoming as successful as his father. This often led others to mistake his quietness for arrogance, resulting in bullying and isolation.
Despite this, he possesses a gentle and responsible nature, which was first recognized by a classmate named Hana, and later earned him the trust of members of the Emilia Camp.
After dropping out of high school, Kazuki made a conscious effort to change. He began initiating conversations, using humor to fit into groups, though his social awkwardness often showed through. He has a strong tendency to blame himself for any problem he thinks he could have prevented — a trait criticized by both his peers on Earth and by Puck, Beatrice, Emilia, Subaru, and Rem in the other world.
To overcome his social shortcomings, he began reading extensively about communication and human behavior.
Kazuki prefers cold weather and dislikes heat, often wearing short sleeves even in winter. He is notably prideful, refusing to back down when spoken to condescendingly, regardless of another's status. He views his father as a role model and strives to reach his level of success — yet he is also willing to sacrifice personal goals if it means helping someone in need.
History:
Life on earth:
Kazuki Tanaka was the older brother in his family and the only son of Kazuki Yosuke and Kazuki Luna. His family rarely stayed in one place, spending most of their lives traveling around the world.
From a young age, Tanaka greatly idolized his father, a wealthy innovator known for his inventions and charitable work. He often boasted about being his father's son, proud of his achievements. However, one day his constant boasting led to an incident that left a lasting mark on him. Since then, Tanaka became extremely self-conscious and overly cautious about troubling others, often blaming himself whenever he was even slightly connected to a problem.
After that event, he stopped mentioning his father entirely and retreated into himself, dedicating his focus to achieving his goals. His parents were concerned about the sudden change in personality but were unable to help him. Despite everything, his relationship with his younger sister remained unaffected.
At sixteen, Tanaka's parents encouraged him to attend high school, and he surprisingly agreed. He enrolled in Nada Tokyo High School, earning the highest score on the entrance exam and maintaining perfect grades throughout the year. However, he avoided social interaction, turning down invitations and keeping to himself, which caused his classmates to perceive him as arrogant and led to subtle bullying — most of which he ignored.
One day, a girl named Hana approached him and managed to befriend him. Playful and persistent, she teased him often and convinced him to join the book club. Tanaka gradually grew fond of her, and their friendship blossomed into a mutual crush. His father also praised him for finally making a friend, reminding him that communication is key to success.
Unfortunately, Tanaka's poor reputation caused Hana to become a target of bullying as well. When Tanaka discovered this, he confronted one of the students and got into a fight, resulting in a two-week suspension — after which he decided to drop out of high school entirely.
His decision was harshly criticized by his parents, especially his mother. When he asked to live on his own, they refused at first, but his determination didn't waver. Eventually, his father respected his wishes, and Tanaka moved into a small apartment in Tokyo, living independently for a while. After realizing his father was secretly monitoring him, he relocated to Shizuoka, where he worked part-time and studied alone.
This solitary lifestyle continued for over two years, until one day — without warning — Kazuki Tanaka was transported to another world.
Abilities Return by Death
Tanaka possesses the same Authority as Subaru Natsuki, allowing him to return to a fixed point in time upon death. Their abilities are interlinked — if Subaru dies, Tanaka is pulled into the Shadow Garden and the timeline resets for both, and vice versa.
Penalties:
Attempting to reveal the ability causes a shadow hand to clutch his heart, affecting both him and Subaru.
The ability increases their miasma, attracting Witch Beasts.
Spirit Affinity
Tanaka possesses the highest natural affinity with spirits in the series, surpassing even Emilia and Julius. Despite not forming contracts, spirits instinctively aid him — often to the point of self-sacrifice.
Magic
Initially assessed by Puck as having a Water attribute, Tanaka later demonstrated the ability to cast any element of magic, provided he understands its structure and physical principles.
He is capable of renaming or improvising spells and even bypassing incantations entirely. His pure mana quality amplifies his spell output far beyond the norm.
However, his gate suffers from an unknown issue — it regenerates mana very slowly, causing him to collapse after overuse. Though advised to rely on spirit arts, this reduces his overall power.
Trivia
- Birthday: January 2nd
- In the early story, Tanaka is physically weaker than Subaru.
- After the Ulgarm Incident, he began bonding with Beatrice, who inspired his love for cooking.
- He dislikes sweets, yet frequently makes them for Emilia and Beatrice.
- Despite claiming not to play favorites, Tanaka subconsciously ranks those he cares about — family and Hana from Earth, and Beatrice, Emilia, and Subaru in the new world.
- His biggest fear is cockroaches.
- He enjoys photography, often taking candid pictures of people.
- He played bass guitar on Earth and is a talented singer, unlike his tone-deaf sister — though he insists her singing is "the best there is."