The Primordial System - Chapter 28: Rhythm

As a walk-on, he had been the mistress of his sugar daddy for three year. However, they only had met each other for a few times.
As a boss, his sugar daddy had tons of lovers.
The walk-on: The cake shop is the only thing I love in this world. Lovers? Never want one.
The boss: No problem. Nobody wants that.
Then, they fell in love with each other…
Shameless playboy x heartless rogue
1v1, this is not a decent love novel.

- Description from Novelupdates

The Principality of Atall lies between two great powers: the Kingdom of Allion to the west, and the Holy Dytiann Alliance to the east. Leo Attiel, the second-born prince, was sent to Allion as little more than a hostage, where he studied and trained in the military arts under a frontier general. And now, the times have reached a turning point.

Relations between Allion and Conscon Temple, a neutral land adjoining Atall, have worsened. Percy, sent from Atall as reinforcement; Camus, a warrior monk; and Kuon, a mercenary from a remote region, join forces to resist the looming threat of Allion’s army.

At the centre of the fighting, the three of them and Leo are about to have their fated encounter.

Sano Yuji, a black company employee, is summoned to another world while finishing his work at home. His profession in the other world, a Monster Tamer, is considered a job that makes it difficult to become an adventurer. However, thanks to some slimes he met, which read several magical books, he gained magical powers and the second profession, Sage. Yuji acquired overwhelming power, but is he conscious of his strength? Blindly becoming unparalleled and strongest in the world!