The Blizzard Group Arc

Eleventh in the series and the second arc of the Human Monster Saga, this chapter centers on Fubuki's failed bid to press Saitama into her faction, a fresh clash between Genos and Speed-o'-Sound Sonic, and Saitama's decisive answer to Sonic's newest technique. It closes by handing Saitama and Genos their hero names and turning attention toward Garou's opening rampage.

Three figures cross into a sealed district of Z-City, revealed as the top three B-Class heroes, Fubuki, Eyelashes, and Mountain Ape, closing in on their target. At the apartment, Genos shares that the pair have climbed to B-Class Rank 7 and S-Class Rank 14, crediting eyewitness reports for finally getting his master noticed. He then senses something approaching at blistering speed and slips outside to find Sonic, who has come once more to challenge Saitama as his rival. The two provoke each other into a fight, while indoors Saitama accidentally overwrites the save data on King's game.

Twenty minutes later the three heroes are pounding on Saitama's door. Fubuki presents herself, lectures him on the Association's internal factions, and demands he serve under her. When he flatly refuses, Eyelashes and Mountain Ape attack and are dropped in an instant. Fubuki turns to her psychic powers, unleashing a technique meant to shred bone and flesh, but Saitama slips behind her unbothered and chides her for how she plays the hero. Enraged, she throws every ability she has, then a box cutter, only to be swept into the crossfire of Genos and Sonic and saved when Saitama steps between the blasts.

Genos accelerates far beyond his old speed and keeps flanking Sonic, even snipping off his topknot to leave him with short hair. Saitama, watching alongside a bewildered Fubuki, guesses his pupil has received new parts. Sonic counters with a secret slashing technique Genos cannot track, prompting the cyborg to detonate the whole area at full power. When the smoke clears, Sonic finds Genos already downed and learns Saitama felled him first, to keep his student from wrecking their neighborhood. Saitama then declares he will take Sonic on in earnest.

Sonic launches his ultimate move, a barrage of shadows, but Saitama replies with his own absurd counter, spawning an endless swarm of afterimages and battering the ninja until he seemingly drops, only to vanish and flee. Awed, Fubuki concedes Saitama is simply too strong. She explains she stays in B-Class because she can never match her lone-wolf sister at the summit, so she gathers weaker heroes to surpass her instead, noting that Sweet Mask's grip on the top rank blocks even Atomic Samurai's disciples from S-Class.

Nearby, Sweet Mask is ordered to capture the escaped caveman Suppon alive but kills it outright when it attacks, to the crowd's cheers. Back at the apartment, Fubuki grants that Saitama may be a monster yet ranks him below Sweet Mask and Tatsumaki, and admits she has no real grievance with him even as he refuses to be her subordinate. King then arrives for his game, only for Saitama to sheepishly confess he erased the save. At an Association meeting the pair are finally named: Genos becomes Demon Cyborg and Saitama becomes Caped Baldy, which enrages Sitch, who wants the discussion focused on Garou. Meanwhile Garou downs Tanktop Vegetarian, unsatisfied, and eagerly proclaims his hero hunt.

Genos and Sonic cross swords for the first time, sharpening the rivalry between them. Garou's assault on Tanktop Vegetarian formally launches his hero hunt, setting up the wider crisis that the Human Monster Saga will build upon.