Aside from humbling him, it's pretty funny to see the big villain of the last arc scrubbing floors, which is more atoning than what most villains do after they're defeated.

Source: https://screenrant.com/one-punch-man-scariest-villain-garou-ridiculous/

As such, this story about a hardened cursed criminal atoning for his crimes in a world of sorrow and bloodshed definitely inspired all modern dark shonen in aspects detached from its setting.

Source: https://www.cbr.com/shonen-dark-trio-aot-inspiration/

Rook Kast could have brought back the old ways of Mandalore as a way of atoning for failing her people, especially when they needed her most.

Source: https://www.cbr.com/mandalorian-armorer-maul-sins-theory/

Sure, Jiji broke bad in the name of love, but if this standard is set, there's no telling who could lie and pretend to be atoning.

Source: https://www.cbr.com/sasuke-story-uchiha-heavenly-stardust-chapter-10-jiji-redemption/