As a child picked up by an earl, can he only be willing to be bullied by others and decide his life, and be imprisoned and controlled by a prince? Maybe he can't do anything, he is just the prince's "pet", a waste that the prince can kill at any time when he gets tired of playing with him...
"Since you can't get rid of him, let me help you."
"Who are you?"
"I am you, leave everything to me, and sleep peacefully."
Since you can't escape, then let you be controlled by me willingly
Purpose: Can't write