Dōki-kun serves as an office employee at a Tokyo-based company, establishing a peer relationship with Dōki-chan due to their simultaneous hiring year. His character design lacks visible eyes, preserving visual anonymity. Professionally competent yet generally reserved, he maintains consistent romantic interest in Dōki-chan but struggles with shyness in direct expression. This attentiveness manifests in actions like returning to a restaurant for her forgotten items, assisting her during intoxication by carrying her to safety, and displaying gentlemanly conduct during extended proximity—such as an elevator entrapment exceeding an hour.

Mutual affection defines their dynamic, yet persistent miscommunication and hesitation from both parties create complications. He exhibits visible disappointment during misinterpretations, notably on White Day when he erroneously concluded Dōki-chan lacked romantic feelings for him. Interactions with colleagues include receiving flirtatious attention from Kouhai-chan and Senpai-san, though the narrative emphasizes his unwavering preference for Dōki-chan. A distinct vulnerability emerges through his fondness for cats, which Dōki-chan exploits during a cat-sitting weekend; this backfires when his focus shifts entirely to the animal.

Character development unfolds across the narrative, particularly in later manga chapters where gradual emotional openness culminates in reciprocating Dōki-chan’s confessed feelings. His behavioral patterns feature discreet support during her embarrassing moments, like after she accidentally sent a compromising photo, and workplace interventions when rivals disrupt her connection attempts. The narrative confirms their eventual transition into a romantic relationship, shifting toward mutual understanding while reducing earlier comedic misunderstandings.