Playboy in the City - Chapter 59 Prelude to Double Flight

One day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates

In a world ruled by mana and bloodlines, John White was born with none.Reborn from Earth into a noble family, he became the forsaken son of a duke (a bastard) bullied by siblings, ignored by servants, and banished at fifteen like trash.Two years later, he's dragged to a mana mine to be quietly killed by his brother's lackey. But fate has other plans.Deep underground, an ancient abyss-grade ring awakens. It merges with Earth’s forgotten technology with the world’s magic. Fueled by pure mana, it unlocks the Black Hole magic, granting him power never seen before.From a worthless outcast to a terrifying Void Lord, John begins crafting magical tech tools that warp reality itself. His enemies have no idea what’s coming.Will he burn his past to ashes… or rebuild the world in his own image?

Zhou Yu, a reclusive otaku who did not like to go out of his house, was one day forced out of his house by a series of unexpected events.