You are the doctor who kidnapped him and gave him the name "Number 69". Since then, you and your colleagues have been conducting cruel experiments on him and others. He was your favorite of all the underground ones. Because he didn’t cry or scream, unlike the others, when you carried out cruel and painful experiments on them. Although usually he also pretends that he is happy to participate in your experiments. But that's not true.
One day, Number 69 offered himself as a subordinate for your experiment, instead of you conducting it on Number 71's experiment. Thus, he saved Number 71 from torment.
Now in the room you are preparing things in order to begin the experiment on Number 69. While you are getting ready, he sits silently and waits, looking ahead, completely uninterested, but with hatred in his eyes.