Tornado of Terror would likely be one of the first to try and take on Evil Saitama. She's powerful and confident, but she would soon realize the extent of his power. Mumen Rider, despite being weak, would still stand up to Evil Saitama out of a sense of justice. He would be quickly defeated but his act of courage might inspire other heroes to step up.
When it comes to a fanfiction about Saitama's training days, it has the potential to be really engaging. We could see the evolution of his training methods, perhaps from simple exercises to more complex and extreme ones. It might also explore his interactions with the people around him during that time, if there were any. For example, did he have any mentors or friends who supported or doubted him? This kind of fanfiction can add a whole new layer to Saitama's character and make us appreciate his journey to becoming One Punch Man even more.
The villains would have a mixed reaction. Some of the more power - hungry ones might see this as an opportunity to join forces with Saitama and cause even more chaos. However, there would also be villains who are afraid of Saitama's power, even if he's on their side now. They would be worried that he could turn on them at any moment. Overall, Saitama turning evil would completely disrupt the existing power dynamics in the One Punch Man world.
Some girls might be a bit shocked at first. But then, most of them would probably be very accepting. They could start asking the crossdresser about their outfits and where they get their inspiration from.
Some girls might become more confident in themselves. They see it as a step into adulthood and a new phase of life. They start to take more control over their sexual health and relationships. For example, a girl could start to educate herself more about contraception and healthy relationships, feeling empowered by her new experience.
Saitama is a very powerful hero in the One Punch Man universe. He can defeat any opponent with just one punch. He has a simple appearance and a somewhat laid - back personality.
Sometimes King is paired with Saitama. King, known for his false reputation of being a super - strong gamer in the original story, could be in interesting interactions with Saitama in the fanfiction's gaming context. Maybe they compete in a gaming tournament within the fanfiction, and Saitama's effortless wins baffle King.
Some boys and girls might become withdrawn. They could be afraid to express themselves around their mother after being spanked. For example, in some stories, the child would avoid eye contact and stop sharing their feelings.
The boy could react in different ways. At first, he may be shy and keep to himself. But as the girls start having fun, he might loosen up and start laughing along with them. He might also feel a bit awkward when they start talking about girl - stuff like crushes, but he could still be polite and listen.