Tenma Koizumi, Miya Igarashi’s childhood friend, shares a deeply entrenched bond with her predating the series’ events. Positioned as a romantic rival to Kazuya Hasukawa, he contrasts Kazuya’s sincere yet clumsy efforts with a steadier, more conventional demeanor. Miya’s mother overtly endorses Tenma as her daughter’s ideal match, amplifying societal and familial expectations that pressure Miya to uphold their preexisting connection.

Miya’s eventual choice of Kazuya over Tenma defies these external influences, emphasizing Tenma’s function as a narrative foil. His presence underscores the story’s exploration of tradition versus individual agency, particularly in romantic pursuits. Interactions between Tenma and Kazuya accentuate the latter’s emotional maturation, as Tenma’s composed rivalry challenges Kazuya to confront insecurities and assert his resolve.

Tenma’s role remains narrowly defined by his rivalry and relationship with Miya, with no elaboration on his personal history or growth beyond this dynamic. His characterization serves to catalyze conflict and highlight thematic tensions without expanding into broader narrative exploration.