Dxd Issei : The Gaming Gear - Chapter 7: []:lamely

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

Lin Dong, who has mastered both the divine medical arts and martial arts, has traveled from the mountains to the city.With divine medical arts in his left hand and unbeatable martial arts in his right, he roams freely in the city.

He is a legendary business powerhouse, a King with a business empire. She is just an ordinary female student. A deal, – a paper marriage, a marriage for four years. Four years later, she turned away fearlessly. She thought that their path would never cross again, but he took her in his stride and refused to let go of everything about her, even interfering with her getting close to other men!

A high-ranking officer in the Marines and a master of both Western and Chinese medicine, Feng Yu Heng is transmigrated with a duang sound to the Da Shun Dynasty.