My Girlfriend is a Zombie - Chapter 744: The Demented Genius

Qin Fen had once been abandoned and broken until, one day, he picked up a liquid metal ball that turned his life upside down.
This is the interplanetary era where Classical and Modern Wushu are competing. Classical Wushu enables followers to grow as powerful as dragons and elephants, whereas Modern Wushu enables followers to freeze monsters or even extinguish erupting volcanoes.
Qin Fen steps onto the stage of both Classical and Modern Wushu while belonging to neither. With the exquisite combination of both Classical Wushu and modern technology, he will pave a way to become a legend.
He is one of a kind, a favored son of heaven.

When Xiao Fei was three years old, he was caught by a man with a sharp-nosed monkey and taught him to cultivate. The old man is Sun Wukong. In the past ten years, he has taught him the eyes of the fire, the copper and the iron bones, and the great product of the immortality… After the learning, Xiao Fei went down the mountain and accidentally entered a noble school. Pure school flowers, the best Lori, Miss Qianjin, beautiful maid… I like to sleep with him. Oh no, it’s a friend.

- Description from Biquge.com.cn (translated)

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.

The idiot Long Gen pretends to be a pig and eats a tiger, takes advantage of the girls in the village, travels across the countryside and forests, monopolizes the beauty and coquettishness, and achieves the legend of “Dragon Gen”. There is a widow in front of the door leaning on the door to watch, and a sister-in-law next door looking through the screen window… This book is determined to be a stallion, with the goal of pushing down and being pushed.

- Description from novelbuddy