He is Lovestruck in the Revenge - Chapter 310 - Gu Yihuan and Pang Zijin Extra Story 4

A man who had emerged from the world’s most secure prison—God of Death Island, known as a super-powered being called the God of Death, had grown tired of the bloody storms abroad and now, like a hidden dragon, he had returned! But due to an accident, he became the contract husband of a beautiful CEO! From then on, he ruled the city, crushed the petty and wicked, and embarked on the tyrannical journey of an urban legend!

When Shen Xinghui, an ordinary young man, is suddenly transported to a fantastical world, he finds himself surrounded by incredible beings like Beast Man, Dragon Man, and even Demons.Struggling to adapt in a place where the rules of life, magic, and even biology are wildly different, Shen Xinghui must rely on the guidance of Ignatius, a noble Dragon Man.As Shen Xinghui learns about this world’s diverse cultures, powerful magic, and the ever-present mystery of how he arrived, he discovers that he’s not the first outsider to find himself here—and perhaps not the last.With no clear way back home, Shen Xinghui embarks on a journey to the capital of the Cindralith Kingdom, determined to carve out a place for himself in this strange yet wondrous land. Along the way, he uncovers secrets about the world—and himself—that will change his destiny forever.

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.