Reborn as a Vampire in a Dying World: Blood, Power, and Pleasure - Chapter 38: Level Up and Let Go

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

[Mature Smut Contents!]When a deadly virus turns the world into a nightmare, high schooler Ryan gets bitten by an Infected—along with his crush. Facing certain doom, they decide to go out with a bang, losing their virginity in what they think are their final moments.But surprise—they don’t turn. In fact, they’re cured.Turns out, Ryan’s seed has a miraculous side effect: it heals infected women. And that’s not all—he soon discovers unique powers of his own. Now, in a world overrun by monsters, Ryan has a new mission: survive, thrive, and build a sanctuary of powerful (and stunning) women who owe their lives to his very special ability.

If you had a chance to live again, what would you do? Earn money, hold onto a thick leg, just find someone to live a happy life with? Ha ha… Stepping on the beat of the times, riding the wind and breaking the waves, strategizing, using your knowledge to change yourself, and everything around you, come back! The reality flows to the plot, the golden fingers are thick, slow, and cool.

- Description from Novelupdates

A polite and lethargic boy was reincarnated in another world as a vampire bishoujo.