Mamoru Daichi occupies the role of the father figure within a fractured family charged with defending Earth from alien incursions. A half-absent IT professional, his penchant for junk food and materialistic habits are frequently emphasized, often shown clutching snacks or gadgets. Though designated as the group’s navigator during missions, his cluelessness and socially awkward demeanor lead others to dismiss him as unreliable—a perception sporadically contradicted by flashes of latent intelligence and emotional insight.

Heavyset and mild-mannered, Mamoru’s timid disposition drives him to shirk confrontation, with his absent-mindedness and social clumsiness fueling comedic mishaps. Beneath this bumbling exterior lies a gentle, kind-hearted individual quietly determined to prevent the family’s dissolution. His fixation on financial burdens creates recurring friction, as he obsessively tallies the exorbitant costs of their operations, clashing with relatives strained by monetary anxieties.

Mamoru’s subtle yet pivotal evolution sees him shift from a passive hobbyist to an increasingly engaged participant in missions, motivated by an understated resolve to preserve familial bonds. His interactions, though marred by personal insecurities and external pressures, gradually unveil an innate decency and devotion to his unconventional family, anchoring their chaotic dynamic with quiet, steadfast care.