Tomodachi no Imouto ga Ore ni Dake Uzai - Volume 4, Chapter 0: Summary

The two faced number one female spy transmigrates to a different world and becomes an outrageous idiot girl. When she woke up, what she had to face was consecutive blows of the decline of her family clan, her crippled martial skills, and her disfiguration. To protect her family, she must obtain the treasured book, obtain outstanding achievements, summon a dark beast army. Wait and see how in this unfamiliar, dark magical continent, she dies and becomes a demon then steps up to the top, making all of the formidable people in the world bow down to her in respect.

- Description from Novelupdates

Ukei Kaito fought a desperate struggle in order to fulfill his role as a summoned hero. He defeated the Demon Lord and saved the very world, only to meet an end filled but with betrayal. The companions that he’d trusted throughout his journey betrayed him and killed him by sticking a blade through his chest.

Waking up from a hangover, Wang Hao finds himself reborn in an alternate world. To his delight, he realizes that he has a system to help him in this new world. However, his system turns out to be a highly unconventional one. Instead of serving justice and winning the respect of other people, Wang Hao has to do all kinds of bad things in order to make use of the system. So, Wang Hao embarks on the journey to being cursed for good…

Rainer, an amateur arcanist and college student, sought to create a new spell far surpassing the magic of the few he inherited from his grandfather. Yet the interference of an unknown event during the casting of his spell led him to be thrown through space and time.