The Strongest Dull Prince's Secret Battle for the Throne - Chapter 19: Mother of Three

“God, please. If you are real, make my one last wish come true. Let me live.”When Callisto got diagnosed with an incurable genetic disorder at age 5, she was expected to live for only ten more years.With her life on its last leg, Callisto underwent an operation that has a one in a million chance of success called the Mutated DNA Fusion, granting her wish to live. However, the operation gave her more than what she wished for.With her black hair turned silver, cat ears overhead, and a tail from her behind, Callisto now has to live her life as a half-human and half-animal, a catgirl.

Lin Li accidentally enters another world while playing with his smurf mage account just after he maxes out all kinds of crafting skills, bringing with him various top-grade materials. Although his character is practically powerless, what he gains in return is unprecedented magical talent! Can he survive by himself after being thrown into another world?

- Description from Novelupdates

This is a world where a king is the most powerful.