MTL - Undead - Chapter 16 .Chapter 16

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

Yang Yan found himself becoming a corpse. But before he could stay for a minute, the lid of his coffin was opened.A stunning face appeared in front of him.Leng Biyue!As the Holy Maiden of the Fairy Maiden Sect, she possessed the quasi-empire bloodline!Blood spilled from the corner of her mouth, fell, and landed on Yang Yan's face.His eyes opened!“The Sword Dao Emperor, who was buried for 100,000 years, has come to life once again!”

Back to the end of Ming Dynasty, he was reduced to a slave.

This emperor, a beggar can do it, a slave can do it, a bandit can do it, but a house slave can’t do it?

- Description from novelbuddy

High-school student Koremitsu Akagi finds himself attending the funeral of Hikaru Mikado, who had died in an accident during Golden Week. He’s not sure why he’s there, as he only exchanged a few words with Hikaru at school. However, Hikaru doesn’t seem to be completely gone from the world, as he comes back as a ghost in order to fulfill a promise to Aoi Saotome, his fiancée. Since Koremitsu is the only one who can see him, he asks him to carry out his promise in his place.

Complying with his request, Koremitsu tries to fulfill Hikaru’s promises to the rest of his “girlfriends”, helping them overcome past misunderstandings and repair broken relationships.