TV-Series
Description
Executive Officer Yosuke Kadomatsu is the protagonist and second-in-command of the Japan Maritime Self-Defense Force Aegis destroyer Mirai. Holding the rank of Commander, he serves as the ship's executive officer under Captain Saburo Umezu and is a career officer deeply rooted in the ideals of the post-war Self-Defense Forces.

Kadomatsu is characterized by a profound and unwavering respect for human life, which stands as his most defining personality trait. This principle is so deeply ingrained that it consistently overrides strategic or historical considerations, placing the immediate preservation of life above all other concerns. His demeanor is serious and professional, befitting his position, but this exterior masks a core of intense personal responsibility for his crew and for the unforeseen consequences of his decisions.

The primary driver of Kadomatsu's actions is this sense of duty to protect life, a motivation that places him at the center of the series' central conflict. When the Mirai is transported back in time to the Battle of Midway in 1942, Kadomatsu makes the pivotal decision to rescue a downed Imperial Japanese Navy pilot, Lieutenant Commander Takumi Kusaka. This act, born of his humanitarian instincts, directly contradicts the crew's initial vow to avoid altering history and becomes the catalyst for all subsequent events. Kadomatsu feels a heavy sense of responsibility for the changes Kusaka sets in motion, believing he must try to manage or undo the consequences of his own merciful choice.

Within the story, Kadomatsu's role evolves significantly. Initially the second-in-command, he assumes acting captaincy after Captain Umezu is injured, placing the burden of command and the weight of historical decisions squarely on his shoulders. His key relationships are central to the narrative. His bond with Captain Umezu is that of a trusted subordinate to a respected superior. His friendship with fellow officers Masayuki Kikuchi and Kohei Oguri, formed during their time at the Japan Maritime Academy, provides a personal anchor, though their differing viewpoints on how to handle their situation create significant internal friction. Most critically, his relationship with Kusaka is adversarial and complex; Kadomatsu rescues him but then finds himself trying to stop Kusaka's active and often violent attempts to reshape Japan's destiny using knowledge from the future.

Kadomatsu undergoes a marked development as the series progresses. He begins as an officer dedicated to non-interference but is forced to adapt as his actions irrevocably change the past. The paradoxes of time travel strike him personally when a change in history results in the death of his own father as a child, causing Kadomatsu himself to become a temporal anomaly—a man who logically should not exist. This profound personal loss hardens his resolve. He eventually leaves the Mirai on a personal mission to stop Kusaka, and is seriously wounded while protecting the last emperor of Manchukuo, Puyi, from Kusaka's schemes. Later, after being ousted from the ship in a mutiny led by his friend Kikuchi, Kadomatsu mounts a successful effort to regain command, demonstrating his resilience and commitment to his principles even when faced with betrayal. His journey transforms him from a passive actor trying to preserve history into an active agent trying to save as many lives as possible from the ravages of the war he now finds himself in.

As a senior officer on a modern Aegis destroyer, Kadomatsu is a highly skilled naval tactician and leader. He is proficient in the use of standard JSDF weaponry, including the SIG Sauer P220 pistol and the Howa Type 89 assault rifle. His most notable ability, however, is not combat-oriented; it is his steadfast moral compass and the strength to make agonizing decisions under extreme pressure, even when those decisions carry catastrophic potential for the future.