Oathbreaker: A Dark Fantasy Web Serial - Chapter 8Arc 3: : The Mercenary

A mecha otaku is reincarnated into another world as Ernesti Echevalier (Eru). In this world there exist huge humanoid weapons known as Silhouette Knight. Dreaming of piloting those robots, Eru, with childhood friends, Archid Walter and Adeltrud Walter: together they will aim to become a Knight Runner, pilot of Silhoutte Knight.

Between heaven and earth lies the greatest truth, and the manifestation of the great truth descends in the form of Gu.　　People cultivate the Qi of heaven and earth around their bodies to control Gu and exert their magical power.　　One year after his transmigration, Chen Qing finally discovered his special features on the day he contracted his first Gu. He was actually able to see through everything about the Gu...　　Therefore, he began to march toward the road to immortality step by step.

Once time travelling, the talented young master became the idiot of the Gu family who was cut open and her son was taken away by others. Five years later, she came back with a cute baby. – She did it! Expensive jewelry that is popular in Beijing——she designed it!

The top restaurants all over the mainland – she opened it!

Even the most mysterious island of no return is hers!

Miss Gu took her son to eat and drink spicy food, slapped his face and watched the show, so happy!

But one day, a certain man suddenly blocked her door: “Woman, how dare you steal my prince’s son!”

Ha! Want to snatch her son? “Close the door and let the dogs go!”

- Description from novelbuddy

The first time they met they had battled fiercely, just for a mere bunch of herbs. She needed it to save people, and he wanted to use it to save his own life.