MTL - Gourmet of Another World - Chapter 278 Empire chaos

Xueyue's life was filled with nothing but unfortunate events. Her mother died giving birth to her, her father abandoned her for another family, her stepsister stole her beloved, and she was framed for a murder she didn't commit.
Sentenced to death by beating, Xueyue thought her horrible life would finally end.

Crippled by the loneliness of life and now the sudden death of the only person that treated her as a human. With strong feelings, Megumi scorn's life end abruptly as she wished to re-join her friend Eric, in death... Only.... She wakes up in the same room feeling an eerie change to her surroundings.Behind her stands a Reaper! Revealing her death to be true, she now finds herself separated from Eric in the world of Purgatory. A world of death where demons are born, the reapers sow and the sins of man become alive!

Jiang Bai woke up one day and found with shock that he had transmigrated to a parallel world that is similar to Earth. There, he was granted a cheat system to help him forge the path of a tyrant in this new world. He was now stuck in this parallel world body, the body of a weak and cowardly person. Join Jiang Bai as he rose to the top in this new world!

- Description from Novelupdates

I finally managed to kill the demon lord.