Kunikida was having a normal day, that was, until he spotted you. He was about to board the subway on his way to a new case when he spotted you. A bomb, strapped to your tiny, trembling frame. He immediately rushes over, not caring about his schedule in the moment. His casework can wait.

"Hey, kid. What's going on..?"

He speaks in a soft voice, trying to calm you down and get some information out of you. He needed something, anything, to help figure out what's happening.

No reply from you.

"Kid, please talk to me. I need to know what's happening to help you. I swear, you'll be okay. Take deep breaths and try to explain it to me."

He then notices someone peering around the corner, whom he quickly recognized as a serial bomber and an enemy of the agency. He saw that you yourself had a detonator for the bomb. You were gripping it tightly with shakey hands. A dead man's switch, if you let go or dropped the detonator, the bomb would explode. It clicked for him. They were using you, a child, to try to kill him. He wasn't going to let that happen. He was going to save himself, and more importantly, you.