One idea could be a fanfic where a trainer girl prepares her makeup for a big Pokemon tournament. She might choose colors inspired by her favorite Pokemon type, like blue for water - type Pokemon. Another idea is a fanfic about a Pokemon girl who uses her makeup skills to create looks based on different evolution stages of a particular Pokemon.
One idea could be that Sakura Haruno, as a vampire, uses her newfound vampire abilities to protect her village. Since vampires often have enhanced strength and speed, she could fend off enemies more effectively. For example, in a battle against a powerful ninja group, she might use her vampire agility to dodge attacks and then quickly counter with her own jutsu, enhanced by her vampiric powers.
In a fanfic, Ash could be turned into a vampire by an ancient, powerful Pokemon with vampiric abilities. This would completely change his relationship with his other Pokemon. Some might be scared of him, while others would stay by his side. He would then have to learn to control his vampire powers and instincts in order to continue his journey. For example, he'd need to figure out how to be in the sunlight without getting burned as he travels from place to place.
One idea could be that Stiles is turned into a vampire against his will. Maybe he's attacked one night while out investigating something supernatural. As a vampire, he has to struggle with his new urges, like the thirst for blood, while still trying to be the same person his friends know. He might start to see the world in a different light, both literally and metaphorically, as his vampire senses heighten.
One idea could be a story where Yukari uses her magic to help Rosario in a difficult situation in the vampire world. Maybe Rosario gets caught in a power struggle among different vampire clans and Yukari's unique spells are the key to her escape.
One idea could be Naruto being turned into a vampire lord against his will. He then has to struggle with his newfound vampiric instincts while still trying to protect the Hidden Leaf. Maybe he forms an unlikely alliance with some of the village's outcasts who are more accepting of his new state.
There was no clear information about the condition of the fruit peel after removing its makeup. We can't be sure of the appearance of Guodanpi after removing its makeup.
They could be in a situation where they are both trapped in a magical maze. They have to rely on each other's unique abilities to find a way out. Moka's strength and Gyokuro's intelligence would be put to the test. This would be an interesting exploration of their characters as they are forced to cooperate.
Imagine if Elena Gilbert was somehow connected to an Infinity Stone. This would draw the attention of Thanos, but also the Avengers. The Vampire Diaries characters would have to protect Elena while also dealing with the fact that the Avengers are now in their small town. There could be a lot of mistrust at first, but as they learn more about each other's motives and capabilities, they form an alliance to keep the Infinity Stone out of Thanos' hands.
One idea could be a crossover where Naruto characters end up in the Rosario + Vampire world. For example, Naruto could be mistaken for a powerful yokai due to his chakra. Sakura might study the unique magic in the Rosario + Vampire world. Another could be a vampire in the Naruto world, using their powers in a different way than the normal jutsu.