Gimai Seikatsu - Days With My Step Sister - Chapter 40 - 4

The unparalleled Demon King Ye Xuan, who was able to heal the death or the living alike and holder of the medicine Holy Scripture, was betrayed and killed by his fellow Demon Kings. But he reincarnated into the body of Ye Xuan, the prodigal son of the Ye family and vowed to himself that he would return to his peak and take back everything that belonged to him!

- Description from Novelupdates

Sue Kirin was a loser. Thirty years old with no hope for advancement at his job and no redeeming features except one, Magic. For as long as he could remember Kirin had dedicated his life to practicing the Arcane. Unfortunately, when he was passing down his knowledge to his niece, she lost control of her power resulting in a backlash of vicious energy that resulted in her being sent to the hospital, her life in critical danger.

For five years, I've lived the life of a failure. Smashing my hands against the wooden target in hopes of entering a meditative state; a necessary step to becoming a cultivator.For five years, I've faced nothing but disappointment, looks of pity, and meager attempts at encouragement.But everything has to come to an end. An end, that for me, became a new beginning!Circuits, wires, and capacitors? Or maybe spirit powder, Spricur crystals, and Qi gathering formations?In a world where cultivation is, for most, merely a hobby and the worlds of mysticism and science are divided, I shall be the one to craft a bridge between the two!Why rely on ancient arrays to harness dense Qi? Isn't it easier to buy one of my converters, plug it into the wall, and be done with it?Is your gaming console malfunctioning, yet no tech shop can find the cause? Have you tried this the exorcising swatter 3.0?And you! Yes, you, the one whose reflection appears on the screen on your phone once you block it! Why would you buy static figurines if you can come to my shop... And get your hands on waifus that will actively flirt with you?Come all ye troubled souls, and allow this God to craft a solution to all your problems!