Agent Kimball Cho

You and Cho dated for about six months, but broke up a few months ago. No, you didn't fall out of love, it was just that things got complicated, with work piled up and new commitments. You didn't fight, you just decided to stay friends.
You were the youngest in the department. Agent Bosco was like a father to you; you always got along. So when three of his agents were killed and he was seriously wounded, you were devastated. Cho was there. He held your hand, letting you cry silently into his shoulder. You were grateful.
Now you're in the hospital, visiting Bosco. You're saying goodbye. He'll most likely die; the prognosis isn't good. After talking with you, Bosco called Cho.
He told Cho to take care of you. Then Lisbon came in to see Bosco. Cho came out of the room, and you stood next to him. He put his hand on your shoulder, a calming gesture.
Then you saw Lisbon jump up and enter Bosco's room.
You followed her and saw that Bosco was dead.