Kain

Kain is a boy who works in the Accounting Department of the Life Management Bureau, known as a Marker of Life Spans. He manages human lifespans and wears glasses on duty, which allow him to take on a physical form, much like Rinne’s haori or Ageha’s ribbon. On the surface, he is a calm and handsome young man, but he is actually sharp-tongued and often cruel. Kain comes from a troubled background due to his mother's extravagant spending and Sabato Rokudo's machinations, leaving him in poverty. His relationship with Rinne Rokudo is hostile, particularly after failed attempts to seize Rinne's lifespan over debts. Despite his cold demeanor, Kain has a certain sense of propriety toward ordinary humans. Over time, he shifts from a serious character to a more comedic one, especially after partnering with Suzu, his contract black cat.

Kain sports a refined and composed look, often appearing very calm and collected.

He wears glasses while working, which have the special ability to make him physically present in the human world.

Outwardly calm and poised, Kain is actually sharp-tongued and harsh in his judgments.

He can be cold-blooded, even prepared to take Rinne's life as revenge for his family's financial misfortunes.

However, he is not entirely without moral standards, refraining from harming ordinary humans such as Sakura Mamiya.

While previously seen as a serious character, Kain evolves into a public servant who easily covers up mistakes and becomes more of a comedic figure after Suzu enters the story.

Kain is responsible for managing human life spans in the Accounting Department of the Life Management Bureau.

His mother, a frequent victim of Sabato Rokudo’s schemes, dragged the family into crippling debt. As a result, Kain could not attend his dream high school and harbors a strong grudge not only against Sabato, but also against Rinne, who was made a co-signer on these debts.

He now lives in poverty with his mother and Suzu, frequently facing hardships like utilities being cut off due to unpaid bills.

Kain's glasses can materialize his presence in the human world, similar in effect to Rinne’s haori or Ageha’s ribbon.

As a Marker of Life Spans, he is directly involved in the administration and management of human lifespans, giving him a bureaucratic yet critical supernatural role.

Kain has a hostile relationship with Rinne Rokudo, consistently causing trouble for him whenever they cross paths.

He lives with his mother and Suzu, enduring a poor lifestyle due to his mother’s extravagance.

He holds animosity toward Sabato Rokudo for ensnaring his family in debt and also dislikes Rinne, who was roped into the situation as a guarantor.

Kain is a senior to Renge Shima from shinigami middle school. Though aware of rumors about her being a Damashinigami, he chooses not to believe them due to her denial and his knowledge of her character. Deep down, he despises Damashinigami, but tries to turn a blind eye when it comes to Renge.

A Life Marker's Mission and Rivalry

Kain begins as a serious and composed Marker who manages human lifespans in the Life Management Bureau’s Accounting Department. His sense of duty is deeply affected by personal grievances—namely his family’s financial downfall caused by Sabato Rokudo, which leads Kain to resent both Sabato and Rinne.

Attempt to Seize Lifespan

Driven by this resentment, Kain once attempts to confiscate Rinne’s lifespan as collateral for Sabato’s debts. However, Rinne’s acquisition of the Wheel of Judgement prevents Kain from taking further action. This event intensifies the antagonism between the two and sets the stage for frequent clashes whenever they meet.

Changing Dynamics and Comic Relief

Initially one of the story's few serious characters, Kain’s dynamic begins to change with the arrival of Suzu, his contract black cat. As the story progresses, Kain adapts to new circumstances, becoming more of a comedic character, often portrayed as a beleaguered but crafty bureaucrat who tries to sweep troubles under the rug.

Life With Family and Ongoing Struggles

Now, Kain shares a home with his spendthrift mother and Suzu, mirroring Rinne’s impoverished lifestyle. Despite hardships like electricity being shut off, he continues trying to manage both his work responsibilities and the chaos of his personal life.

Despite his cold and calculating nature, Kain possesses enough integrity not to harm ordinary humans during his work.

His role shifts from a rare serious figure in the story to a well-loved comic relief character.

His glasses, the source of his physical manifestation, are central to his work identity.