No, it is not appropriate. Writing fanfic that involves nudity in a sexualized way about a character is unethical and violates the boundaries of respect for the character and the source material. It also may not be suitable for a general audience and can make others uncomfortable.
One common theme is empowerment. Since Bakugou is already a strong character, in the female version, it often focuses on her breaking gender barriers in the hero world. For example, she might face discrimination at first but then prove herself to be even better than male heroes.
One great female Katsuki Bakugou fanfic is 'The Hidden Strength'. It focuses on a female version of Bakugou in a different world where she has to prove herself among male heroes. It shows her fierce determination and unique quirk usage.
The plot could be about Bakugou getting exposed to some sort of gamma - like radiation that gives him Hulk - like powers. He then has to figure out how to control it while still being himself. Maybe he accidentally destroys some things around him at first, and has to face the consequences. Along the way, he could team up with his friends to fight against villains who are now even more afraid of this new, super - powerful Bakugou.
One great Bakugou Katsuki hurt comfort fanfic is 'Healing the Explosive Heart'. In this fic, Bakugou gets injured during a battle and his friends, especially the main character, help him through the physical and emotional pain. The author does an amazing job of showing Bakugou's vulnerability, which is a side not often seen. It's filled with heart - warming moments of comfort and growth.
A great way to develop their relationship is through shared traumas. Maybe they both had a difficult experience during a villain attack. They could open up to each other about their fears and insecurities during that time. This vulnerability would bring them closer together. Additionally, they could participate in a hero competition together. As they face tough opponents, they encourage each other and celebrate their victories, which deepens their bond.
I'm not entirely sure if there's a specific 'Naruto father of Katsuki Bakugou' fanfiction. There are so many fan-created works on the internet that it's hard to keep track of them all. It could be a really interesting concept though. Naruto has his own set of values and abilities from the Naruto universe, and Bakugou has his distinct personality in My Hero Academia. Combining them in a father - son relationship could lead to some really unique storylines, like Naruto teaching Bakugou some ninja techniques and how that would influence Bakugou's hero training.
Well, it could be really exciting. Bakugou already has an explosive personality, and if he had the powers of the Hulk, it would be chaos. Maybe he'd struggle to control the Hulk - like rage even more than he does now. He might use the Hulk's strength to be even more of a force in battles, but also have to deal with the destruction that comes with it.
The hurt part should be believable. It could be physical like an injury from a fight or emotional like feeling betrayed. And the comfort should be genuine. It can't be just a quick fix. His friends or the person comforting him should really dig deep into his issues. In some fics, when Bakugou is comforted by someone who truly understands him, like Midoriya, it makes for a great read.
Bakugou in lemon fanfiction usually retains his explosive nature, but it can be channelled in different ways. For example, his determination might be shown in his pursuit of a romantic interest. He may also be portrayed as having a softer side that only a few get to see, especially in more intimate moments within the fanfiction.