An unnamed male Kyoto University student, known only as "I" or "Watashi," begins his studies yearning for a "rose-colored campus life" of popularity, meaningful bonds, and romance with a "raven-haired maiden." Tall and lanky, he has pale skin, gray-blue eyes, black hair, and glasses, typically wearing a white collared shirt with blue pants. His personality blends self-centeredness, social awkwardness, indecisiveness, and bitterness, often blaming failures—especially club choices—on external factors rather than his passivity or poor judgment.

His unreliable perspective distorts others to match his biases: trickster Ozu appears demonic, while film club president Jogasaki seems a tyrannical overlord. These distortions manifest visually through rose-tinted fantasy sequences or cubist panic imagery. His university experience fractures across timelines reset after joining clubs like the film circle, tennis club, or cycling association, each ending in disillusionment. Core figures persist: Ozu, who drags him into schemes; engineering student Akashi, whom he idolizes but fears pursuing; and enigmatic senior Higuchi. Relationships follow rigid patterns—resenting yet relying on Ozu, failing to confess to Akashi, and seeking guidance from Higuchi or a fortune teller. Recurring events include losing Akashi’s mochiguman keychain and aiding Ozu’s destructive plots, like stealing Jogasaki’s love doll Kaori.

Trapped in a time loop within his 4.5-tatami apartment, he mentally reviews his timelines and recognizes his "rose-colored life" failed because he avoided confronting his passivity, blame-shifting, and inability to value existing bonds. He realizes Ozu remained a loyal friend across all realities, while Akashi reciprocated his feelings long before the final timeline. This breakthrough corrects his distorted perceptions, revealing Ozu’s true appearance.

In *The Tatami Time Machine Blues*, he maintains a stable relationship with Akashi. When their air conditioner remote breaks, he proactively collaborates with Ozu and others to alter the past via time machine, demonstrating newfound initiative. The narrative reveals their future son Tamura will time-travel to meet them. His journey concludes by understanding fulfillment requires engaging the present, not fixating on idealized paths. The fortune teller’s recurring advice—to seize the opportunity "dangling before his eyes"—symbolizes his acceptance that happiness demands active participation in reality.