How could a B hero class like Fubuki defeat a dragon level villain?

Question

In the webcomic, Fubuki battles

Psykos

and defeats her. How could a B hero class like Fubuki defeat a dragon level villain?

Answer 1

Well if you've read the chapters concerning the battle then you should know how she wins. It spends most of the chapter where she wins telling you exactly how she wins, right down to the mechanics.

First, don't forget that Fubuki is intentionally remaining B-class because she doesn't want to compete with Sweet Mask in A-class or her sister in S-class. Her class is not indicative of her true strength. Indeed, in general the ranks of heroes and monsters are both not necessarily accurate. The anime and manga spend a little bit of extra time pointing this out, having a low-ranked and seemingly puny-looking monster turn out to be very strong, while you are explicitly told there are cases like this where the rankings are inaccurate. Second, as I said, the chapter spells it out for you:

She uses the move she calls "psychic whirlwind". It details that normally psionic powers follow the path of shortest distance. But she learned to control the path her powers take, and creates a whirlwind of psionic power around her. So instead of her powers clashing head-on with Psykos's and getting crushed—because Fubuki does plainly admit that Psykos is stronger than her—they instead deflect Psykos' attacks harmlessly away. Psykos subsequently wastes her energy, exhausting herself until she's easy pickings.

In other words, Fubuki wins because a fight isn't strictly about power. Fubuki has the superior skill and compatibility to come out the victor.