The unnamed male protagonist, known only as "Watashi," is a third-year Kyoto University student. He initially enrolls yearning for an idealized "rose-colored campus life" and romance with a "raven-haired maiden," but faces disillusionment as reality falls short. Physically, he is tall and lanky with black hair, pale skin, blue eyes, and typically wears glasses, a white collared shirt, and blue pants.

Trapped in recurring narrative loops across multiple timelines, he repeatedly joins different student circles—the tennis club, film society, literary circle, and clandestine organizations—each time hoping for a better outcome. These choices consistently lead to similar disappointments, often influenced by his acquaintance Ozu, whom he perceives as a demonic or impish figure. This pattern stems from his "Grass Is Greener" mentality, believing a different choice would yield his ideal life. Despite resenting Ozu's manipulations, he remains dependent on their friendship, the only constant relationship through the timelines.

His romantic interest focuses on Akashi, a stoic, rational second-year engineering student who fears moths. He repeatedly fails to act on his feelings or return her lost mochiguman keychain, symbolizing their missed connections. Internally, he battles his libido, represented by a cowboy named Johnny, and grapples with his self-image as a bitter "Black Cupid" who sabotages relationships.

A significant shift occurs when he becomes trapped in a metaphysical tatami maze embodying his isolation and regret. Here, he grows a "Beard of Sorrow" and confronts his failures. Escape requires rejecting the pursuit of idealized alternatives and accepting his current reality, including imperfect relationships with Akashi and Ozu. This realization ends the time loops.

In a later narrative sequel, he participates in a time-travel incident involving a broken remote control enabling a time machine. His actions across past and present timelines inadvertently cement his future with Akashi. This outcome is evidenced by Tamura, a student from the future strongly implied to be their son, confirming his eventual romantic relationship with Akashi and suggesting personal growth beyond his earlier insecurities.

Throughout his journey, he serves as an unreliable narrator whose biased perceptions shape the story's visual style—characters appear distorted based on his views, such as Ozu seeming demonic or authority figures appearing tyrannical. His rapid-fire narration reflects anxious thinking. His development culminates in recognizing the value of authentic connections over idealized fantasies.