Nariyuki Yuiga, a third-year high school student from a financially strained household, strives to earn a scholarship that would alleviate the burden on his widowed mother and younger siblings. His academic rigor, rooted in his late father’s advice to cultivate empathy through understanding others’ hardships, drives him to maintain over-80% grades via tireless studying.

Tasked with tutoring peers Fumino Furuhashi, Rizu Ogata, and Uruka Takemoto, he tailors structured lessons to address their academic gaps while managing teacher Mafuyu Kirisu’s chaotic home life through routine chores. He further supports Asumi Kominami, a rōnin student pursuing medical school, balancing these roles with methodical precision.

Earnest and emotionally reserved, he overlooks romantic signals from the girls despite their deepening attachments, yet demonstrates sharp intuition in academic and familial contexts—resolving tensions between Fumino and her estranged father or deciphering Rizu’s difficulty conveying emotions. Pragmatism defines his daily choices: frugal meals like bread crusts, deferred personal ambitions until his family’s security is assured.

Divergent storylines explore shifting relationships. One path reconciles Uruka’s childhood affection as he reciprocates after recalling her solace during his father’s passing. Another fosters Rizu’s emotional maturity through collaborative work at her family’s udon shop. With Fumino, mutual academic challenges and latent attraction evolve into a collegiate partnership. His rapport with Mafuyu transitions from mentorship to shared educational passion, while Asumi’s arc bonds them through resourcefulness on a secluded island.

Family obligations anchor his decisions, evident in sacrifices for younger siblings like Mizuki—skipping meals to fund their necessities. His father’s teaching legacy steers him toward education, embracing perseverance and guidance as core values.

Physically, he sports brown eyes, black hair, and glasses adopted in junior high. Academically adept yet athletically inept, his comedic mishaps often lead to accidental romantic encounters. Domestic skills in cleaning and sewing offset occasional social awkwardness.

A multiverse framework examines alternate realities, each underscoring his adaptability and empathy. Universally, he uplifts others through academic mentorship, emotional solidarity, or familial devotion, solidifying his role as an unwavering catalyst for growth.