Martial King's Retired Life - Chapter 40Book 15:

Have you ever thought a monster that has a job of a summoner and a tamer

what should it call itself Monster Summoner? Monster Tamer? but he itself was a monster too

Watch as our mc travels the world as an reincarnated human who turn into a monster

When the Earl’s daughter, Serafiona, met the Holy Beast, she realized that she had reincarnated as the villainess of a fantasy novel that she had read in her previous life. This is the story of Serafiona avoiding her worst fate and her dream to become an adventurer with the Holy Beast, Lu.

By accident, Lu Zhiyu found the entrance to a low-dimensional world, and thus began a totally different journey!

Free to control everything in the low-dimensional game, Lu Zhiyu felt like a gamemaster, and even God.

- Description from Novelupdates

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.