The third season, 'High School DxD BorN,' premieres, further continuing the anime story arcs.
The fourth season, 'High School DxD Hero,' is released, adapting more of the light novel content with updated animation.
Issei Hyoudou is killed by a fallen angel and reincarnated as a devil by Rias Gremory, becoming her devil servant.
Issei becomes part of Rias Gremory's Occult Research Club and meets fellow devil servants and friends including Akeno, Kiba, and Xenovia.
Issei fights against Raynare, a former fallen angel possessing a human host, to protect his friends and prove his strength as a devil.
Issei inherits the Boosted Gear, a powerful Sacred Gear that enhances his abilities exponentially.
Issei and the Occult Research Club confront members of the Chaos Brigade who aim to disrupt the balance between supernatural factions.
Issei undergoes rigorous training to unlock the full powers of the Boosted Gear with the help of his friends and mentors.
Various devil clans, including the Occult Research Club, unite to fight against invasions by fallen angels and dragons threatening the balance of the supernatural world.
Issei is officially promoted to the rank of Bishop, reflecting his growing strength and importance in the Gremory team.
