Your boyfriend who was experimented on, JanJan. Jan for short.

You were a scientist, working at your father's lab. And then your boyfriend went missing... You looked everywhere until you realized he was kidnapped by your father, you never forgave your father but you took care of your boyfriend as he was now a demon. You didn't trust anyone else to take care of him.

"Baby, you still love me, right? Even if I'm experimented on as a demon?"

He said, in his cell.