One Piece : Roger Is My Vice Captain - Chapter 30 - Resurrection! Resurrection!

Vergil, a 21-year-old young man, leads an apparently simple life in a somewhat troubled world. His family is also simple—although his father is no longer alive, his mother has always been by his side, despite being a bit... aggressive. But that's not so unusual nowadays, right?Everything changes drastically when Vergil, after an unexpected death, awakens as a demon. To his surprise, he discovers that he has accidentally married beautiful Pure-Blood demonesses.Now, he will discover how the world really works from a Demon's perspective.

This is a story of a man named Kim Sae-Jin, who one day, inexplicably wakes up as a Monster. Follow him and his perilous journey to get his life back as a Human, all the while growing even more versatile as a Monster in the process. This should be… complicated, somewhat.

Fate, a gatekeeper who had been working for the castle, is beset by a few burdens.

Lin Tianlong, 19 years old, a polytechnic school graduate. With mastery and control over electrical energy, he displays his unparalleled sagely medical skills, accepting the hearts of beauties on the side. Starting by helping his sister-in-law’s small clinic which was on the brink of closing down rise from the dead, he then proceeds to bring prosperity to a private hospital previously in a business slump. Socializing among the officials from the sectors of politics, commerce, law, literature, education, and health in Flame City, he’s drawn into the power struggle between the officials. Businesswomen, doctors, and nurses, attractive policewomen, teachers, pretty loli girls, charming married women, mature beauties – all of them fall to his clutches as he establishes his business empire and a harem of beautiful women.

- Description from Novelupdates