One common theme is the power dynamic. Fat Gum has a lot of strength and experience, while Fem Kirishima might be portrayed as more of a newbie or someone looking to learn from him. Their relationship can develop around training and growing stronger together.
You can start by looking on fanfic websites like Archive of Our Own (AO3). It has a large collection of My Hero Academia fanfics. Just use the search function and type in 'MHA Fem Kirishima x Fat Gum' and you'll likely find a bunch of relevant stories.
In fanfiction, if Naruto ate the Gum - Gum Fruit, he would likely gain some really interesting abilities. He could stretch his limbs like Luffy from One Piece. This would give him a whole new fighting style. He might be able to stretch his Rasengan - holding hand to surprise his enemies from a long distance. Also, his acrobatic skills would be enhanced as he could use his stretched body parts to swing around like a slingshot.
Naruto's character would become more versatile. With the Gum - Gum Fruit powers, he'd be less reliant on just his chakra - based techniques. This could make him more confident in different situations. He might start to see battles from a different perspective, one that combines his ninja skills with his new stretchy powers. His carefree nature could be enhanced as he has fun exploring his new abilities.
To get gum base in Cave Story, keep an eye out for secret areas and interact with non-playable characters. Sometimes they might give you hints or directly offer the gum base as a gift. Also, defeating certain bosses could lead to obtaining it as a loot drop.
Well, finding the gum base in Cave Story can be a bit tricky. You might want to check hidden rooms, secret passages, or areas that require specific actions or items to access. It could be anywhere, so keep your eyes peeled!