I'm bound to the witch of death

After Xia Feng traveled through time, his heart was inexplicably ripped out.
Instead, there is a crippled evil heart with only enough activity to last for eighteen years. This is a magical heart that can synchronize the target's strength.
In order to survive, he bound the future villain, the Witch of Destruction, who was destined to destroy the world.
The stronger the World-Destroying Witch is, the stronger he becomes!
Then Xia Feng realized that she really didn't blame me for provoking trouble: "Miss Witch, I admit that you are very strong, but you are not strong enough!"