Kiri Victorvich Putin, often referred to simply as Kiri Putin, is one of the two protagonists of the story and serves as a Chronos Ruler, known specifically as the Splash Ruler. He is the teenage son of Victor Putin and the late Mina Putin. At the start of the narrative, the pair initially appear to be brothers, but this is later revealed to be a misconception stemming from Victor’s condition.

In terms of personality, Kiri is presented as a stark contrast to his father. He is a very serious, composed, and level-headed individual who often finds himself irritated by Victor’s playful and irresponsible antics. Possessing a sharp tongue and a logical, methodical approach, he acts as the responsible party in their dynamic, frequently trying to keep Victor focused on their mission. Kiri’s core motivation is deeply rooted in his family’s past. He seeks to restore the time and memories his father has lost due to a curse from a time-devouring monster known as a Horologue. Beneath his exasperation with Victor’s current behavior, Kiri wishes for his father to regain his more caring and mature attitude from before his memories were taken.

Kiri’s role in the story is defined by his mission to hunt Horologues alongside his father. These monsters are born from human regret and feed on a person’s time, causing them to grow younger and lose their memories. Because Victor continues to lose his memories and age backward as a result of a past injury, Kiri takes on a protective and guiding role, effectively acting as the more mature figure in their relationship while trying to recover the father he once knew. His key relationships are centered on his family, primarily his difficult but loving bond with his father, Victor, and his connection to his mother, Mina, whose reappearance complicates the family dynamic.

As a Chronos Ruler, Kiri possesses a Time Covenant, an orange sphere that grants him his abilities, which is embedded in his scabbard. His power allows him to manipulate time specifically through the medium of water. Using his abilities, he can slow down the time of water to create a solid blade for his sword or form defensive barriers. He can also speed up the time of water, launching drops with force akin to bullets in a technique called Thousandfold Drop Rain. In combat, he commonly employs a sheathed sword filled with water and carries multiple water bottles for emergencies. Kiri is also a highly skilled swordsman, proficient in Iaido, the Japanese art of quick-draw combat, allowing him to engage enemies effectively even without his time abilities. Furthermore, due to his mother being a direct descendant of the god Chronos, Kiri possesses an unusual trait; he does not age.