Seishiro Nagi.

Nagi is a very lazy and unmotivated person with an outstanding aptitude for football. He's unnaturally talented, with amazing reflexes, good speed, and jumping skills. But he has no interest in going pro or even playing at all at first. As long as he can get a decent job and keep living a lax life, he is content with doing nothing forever and often appears lethargic in his speech and body language. Introverted to a fault, he lives by himself in an apartment his parents pay for with only a pet cactus for company. He was shown to have no friends in high school before meeting Reo, and he frequently got gossiped about or possibly bullied. Even so, he demonstrates no interest in socializing and often has to be dragged into things by others, especially Reo. He initially does not want to put any effort into football and belittles those who are weak and talentless at the game since such things are easy for him. He doesn't even know anything about the best football players in the world, much to the chagrin of his competitors. At first, he is shown as indifferent to playing soccer and becoming the world's best striker, preferring to play video games or skip training altogether. He exhibits behavior like that of a shut-in and may actually be addicted to his phone. He struggles to let go of it when Anri tries to confiscate his items, and Reo is even able to bribe him into playing when he reminds him he can get it back with the goal reward system.

Nagi is a tall young man with a lean but muscular build. He is shown to have medium length white hair that leaves a V-shaped fringe in between his eyes. He has gray-colored eyes with large irises.

Back in high school, Nagi wore a school uniform consisting of a white blazer with a cascading star pattern on the collar, though he wore a dark hoodie under it instead of a dress shirt and tie. He wore the dress pants and dress shoes as well.