Fanfiction about 'Darker than Black: Yin and Hei' can explore various aspects. It might focus on character development, such as delving deeper into the pasts of Hei and Yin. For example, a fanfic could explore how Hei's experiences in the past shaped his current personality and actions in the series.
One interesting crossover could be a scenario where characters from Naruto enter the world of Darker than Black. For example, Naruto's ability to never give up and his positive attitude might contrast with the often dark and morally ambiguous world of Darker than Black. He could potentially influence some of the Contractors there to question their own motives and actions.
One plot idea could be that Naruto characters gain the powers of Contractors from Darker than Black. For example, Naruto himself could have a Contractor power related to his shadow clones, like being able to send his clones to different dimensions for a short time. Another idea is a story where the organizations in both universes collide. The Akatsuki from Naruto and the Syndicate from Darker than Black might have different goals but similar methods of achieving them. They could either fight or try to make an alliance depending on the situation.
Hei is definitely one of the most popular. He has a mysterious aura and his powerful Contractor abilities make him a fascinating subject for fanfiction writers. They can explore his complex personality and his hidden emotions.
One interesting story could be about a new Contractor with a unique power that changes the power balance in the Darker than Black world. Maybe they have the ability to manipulate time on a small scale, which leads to all sorts of adventures and conflicts with other Contractors.
The mystery surrounding November 11 in Darker than Black provides a rich ground for fanfiction. It has an air of enigma that writers can explore further, like what really happened on that day, what secrets are hidden, etc.
One possible fanfiction could be about Hei and November 11 teaming up for a dangerous mission. They might face challenges that test their loyalty to each other and the organization they work for. For example, they could be sent to infiltrate an enemy base where they have to rely on each other's unique abilities to succeed.
Probably a combination of Naruto and Hei. Naruto has his immense chakra reserves and powerful jutsu like the Rasengan and the Nine - Tails' power. Hei, on the other hand, has his Contractors' abilities which include superhuman strength and agility as well as his unique weapon skills. Combined, they would have a vast array of powers at their disposal and would be extremely difficult to defeat.
The unique world - building of the original work also contributes. The concept of Contractors and their powers is fascinating. Fanfiction can play around with these powers, creating new power combinations or exploring the limits of existing ones. For example, a fanfic could show a Contractor with a never - seen - before power and how it affects the balance in the 'Darker than Black' world.