One Punch Man Episode 9 is pretty much the high point of heroism for the anime.
Genos's act of self-sacrifice, throwing away what little chance he has of winning the fight to save one life. He's not there to win, he's there to save.
Mumen Rider's fight against Sea King gets the full conventional treatment - the man with no chance against overwhelming odds who stands up anyway because there are people to defend. And in the end he and the other heroes did buy enough time.
And then Saitama wrecking his own reputation to defend that of the other heroes. Again, self-sacrifice for the sake of others. It's easy to say that Saitama is less heroic since there's literally nothing seen that can harm him physically. But he's certainly vulnerable in other ways and here he shows that he's still just as heroic as he was in the flashback to before he started training.
Which is probably a good thing, given the next arc shows us most of the S-rank Heroes range from anti-hero to villain-with-good-PR...
D for Drakensis
You're only young once, but immaturity is forever.
Genos's act of self-sacrifice, throwing away what little chance he has of winning the fight to save one life. He's not there to win, he's there to save.
Mumen Rider's fight against Sea King gets the full conventional treatment - the man with no chance against overwhelming odds who stands up anyway because there are people to defend. And in the end he and the other heroes did buy enough time.
And then Saitama wrecking his own reputation to defend that of the other heroes. Again, self-sacrifice for the sake of others. It's easy to say that Saitama is less heroic since there's literally nothing seen that can harm him physically. But he's certainly vulnerable in other ways and here he shows that he's still just as heroic as he was in the flashback to before he started training.
Which is probably a good thing, given the next arc shows us most of the S-rank Heroes range from anti-hero to villain-with-good-PR...
D for Drakensis
You're only young once, but immaturity is forever.