What are some interesting plot ideas for a Frozen and Diabolik Lovers crossover fanfiction?

One idea could be a crossover with Vampire Knight. The Diabolik Lovers vampires could interact with the ones from Vampire Knight in a school setting. There could be rivalries over territory or a common prey. Another idea is a crossover with Black Butler. Sebastian could be hired to deal with the unruly Diabolik Lovers vampires, creating a lot of tense and interesting scenarios. A third idea might be a crossover with Ouran High School Host Club. The vampires could accidentally end up at the host club and chaos would ensue as they interact with the flamboyant hosts.

One idea could be that the characters from Diabolik Lovers end up in the Black Butler universe and are mistaken for demons by the characters there. They then have to deal with Sebastian and Ciel while trying to find a way back to their own world. Another plot could involve a character from Black Butler getting trapped in the Diabolik Lovers' world and having to navigate the complex relationships among the vampire boys.

A friendship - centered fanfiction would be cool. Maybe a new character befriends the vampires not out of fear but because they see the good in them. This character could slowly break down the walls the vampires have built around themselves and change their relationships with each other.

One idea could be a crossover where Naruto characters end up in the Diabolik Lovers universe. Maybe Naruto's positive attitude starts to influence the dark and brooding vampires in Diabolik Lovers, leading to some unexpected friendships. Another plot could be a Diabolik Lovers character being sent to the Naruto world and having to adapt to a completely different environment with ninjas and chakra.

One idea could be a crossover where the magic from the Harry Potter world is introduced to the vampires in Diabolik Lovers. For example, a Hogwarts student could accidentally end up in the Diabolik Lovers' world and use spells to both defend themselves from the vampires' advances and also try to find a way back home.

A plot idea could be that Yui gets sick with a strange illness that only Shu can cure because of his unique vampire abilities. This forces Shu to confront his feelings for Yui as he tries to save her. Or perhaps they find an ancient prophecy that involves them and they must journey together to fulfill it, facing many obstacles along the way and growing closer as a result.

The vampires from Diabolik Lovers would likely be divided in their reactions. Some might see the characters from Frozen as mere prey, while others might be more interested in the magic and power that Elsa and Anna possess. There could be power struggles among the vampires as they debate what to do with the sisters. And the sisters would have to use their wits and Elsa's powers to survive in this new and dangerous world.

A plot idea might involve a situation where the kiss is witnessed by one of the other brothers. This could lead to jealousy and conflict among them. For example, if Laito sees the kiss, he might try to drive a wedge between Ayato and Yui out of his own twisted sense of fun and envy. Or perhaps the kiss unlocks some hidden memories for Yui that are related to her past and her connection to the Sakamaki family.

A more unique plot could be set in a modern human world where Subaru and Yui are trying to live a normal life. But Subaru's vampire nature keeps causing problems. They have to figure out how to deal with things like his need for blood in a world where vampires are not supposed to exist. This could lead to some really interesting and emotional moments between them as they struggle to be together.

Another great plot idea is the cultural exchange between the two universes. The proper British wizarding society in Harry Potter and the more gothic, dark world of Diabolik Lovers. How would the characters from each world react to the different social norms? For instance, how would the vampires react to the Hogwarts house system? And how would the wizards deal with the vampires' feeding habits? This can lead to a lot of humorous and also thought - provoking situations in the fanfiction. It can also explore themes like acceptance and prejudice as the two groups interact.