Well, the 'highschool dxd hero light novel' focuses on Issei's journey. He is part of the Occult Research Club at school. There are elements of action, as he has to fight against different factions. There are also romantic sub - plots as he interacts with the female characters around him. The story also delves into the complex politics between the devils, angels and fallen angels. For example, different devil clans have their own agendas and Issei often finds himself in the middle of their power struggles. Moreover, his own growth as a devil in terms of power and maturity is a significant aspect of the story.
Issei Hyodo is one of the main characters. He is the protagonist who becomes a devil. Rias Gremory is also a main character, she is a devil and the president of the Occult Research Club.
Issei is definitely a popular choice. His growth from a perverted high school student to a powerful devil is a great arc to explore further in fanfiction. You can expand on his relationships with other characters, like his loyalty to Rias and his rivalry with other devils.
Perhaps a story where the female characters in 'highschool dxd hero' get a chance to shine more. For instance, Rias could go on a solo mission to prove herself without relying on Issei. This could lead to her discovering new aspects of her own power and also forging new alliances. It would also give a different perspective on the world of 'highschool dxd hero' from a female - centric view.
300 Heroes was a popular role-playing game with many heroes for players to choose from. Here are some of the most popular hero characters:
1 League of Legends: Yasuo
League of Legends: Rui Wen
League of Legends: Robbery
League of Legends: Silas
League of Legends: Kassadin
6 League of Legends: Blade Girl
League of Legends: Xin Zhao
8 League of Legends: Zach
League of Legends: Lee Sin
League of Legends: Thresh
The heroes above performed well in the game and had unique skills and powerful combat abilities that could allow players to win in the game. Of course, players could choose a hero that suited them according to their preferences and game style.
I'm not entirely sure specifically what 'dxd adult fanfic' is. 'DxD' might refer to a particular series (such as 'High School DxD'), and 'fanfic' stands for fan fiction. However, the 'adult' part implies it could be fan - created stories with mature or inappropriate content which is not suitable to discuss in detail.
The number of DxD novels can be a bit tricky to pin down. Different regions might have different releases and editions. Your best bet is to do a comprehensive search on popular book databases or consult with avid fans of the series.