The Fallen Hero Reincarnates as the Demon King's Son - Chapter 25 - 24 - The Deals

Anna a normal girl waiting to have all her dreams come true falls into a deadly trap when she begins to desire someone she shouldn’t. After being shocked to reality of her boyfriends betrayal she dives head first into the flames of sin with the Don of the underworld.
Ren a ruthless cold heartless man lusts for someone he shouldn’t but can’t let go. He just didn“t realize how taboo she was an...

While others transmigrate into the role of a villainous young lady, I, on the other hand, became the ab*sed female lead in a sadistic novel! I’m trembling with anger, but there’s no one to seek justice from! This is a story about a girl who transmigrates into a weak, pitiful, and helpless heroine. With her natural charm, gentle demeanor, and a touch of tea-loving personality, she conquers the hearts of the villainous female leads, ultimately achieving a sweet and satisfying counterattack.

This is a prequel to the anime movie To Aru Majutsu no Kinsho Mokuroku – Endymion no Kiseki.

Just before the completion of the Academy City space elevator “Endymion”, the main characters Kamijou Touma and Index encounter a level 0 girl named Arisa. The Magicians are after Arisa, and they attack Academy City. A female leader named Shattoaura leads a unit from Academy City against the attack. Kamijou and Index learn from Stiyl that Arisa is key to a brewing war between the sides of Magic and Science. When science and magic cross paths, the story begins with Endymion as its stage!

When an era came to an end, various forces set foot in cultivation to compete for immortality. A young boy who spent most of the time sleeping got lucky in the troubled times and became an unparalleled immortal who could cover the sky with a snap of fingers. Was he going to live forever?

- Description from Novelupdates