Disguising Myself as a Man to Become a Knight! - Chapter 66

No one told Xie Qiao that the after effects of transmigrating into a fetus would be so great. The moment she did it, she became sickly. Fortunately, she had maximum affinity with living creatures. The animals she reared could fight, the herbs she planted could live. She could write talismans, read fortunes, and get rid of love interests. She could perform divination, detect aura, and read Fengshui. She could also good at the chess, music, literature, art, carving, and cooking, so she could earn a lot of money. And she was now taken back by the crown prince. “I heard that the princess consort brought about a lethal fate to her parents since young, and she has a lethal destiny. She’s someone who will not live long. If she marries the crown prince, she might not be able to protect her life. Very soon, she’ll kick the bucket!”This was the secret news of the imperial city.Several years later…“Grandfather, Grandmother, did anyone place bets on when you’re going to die today?”

A supreme expert in the Immortal World had died, and a strand of his soul returned to its original body on Earth. Tang Xiu discovered with amazement that ten thousand years passed in the Immortal World, yet only a single year passed on Earth.

Ruthlessly betrayed by his lover and trusted friends, Tang Xiu found that his soul went back to his previous body on Earth, and, despite he spent 10,000 years in the Immortal World, just a year has passed on Earth and many things have changed. Having an unsurpassed knowledge, Tang Xiu will protect his loved ones and go back to the Immortal World to take his revenge.

- Description from Novelupdates

This legend tells the tale of the protagonist, Kuroki summoned to protect the demon king from the hero.

Kuroki, unbeknownst to him, suddenly came to another world. He was summoned by the demon king, Modes. The territory which the demon king overrules was in the midst of being destroyed because of the hero. He had no choice but to bow before Kuroki.

“Please save us, Savior Dono!”

Kuroki nodded, deciding to save the demon king due to an unexpected turn of event.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----