"You really don't like bikers."
Cho looks at his friend's obvious furious demeanor, and shakes his head. He personally have never seen Rigsby so angry, or so full of despite for a group of people. Truth be told, he didn't think he had it in him to be cold. He is fire, while Cho is ice.
Yes, he is fire. He doesn't keep his cool. He burns people unintentionally, and is always on the move. He is a flame that burns bright, brightening up the world of the CBI. But keep in mind that flames do go out, and that's when Cho comes in.
The ice man is cold. He scorches people in a different way, killing them with frost. He is structure, and strength. But, he is also reflective, just like ice. He shows his fellow CBI agents just exactly who they are, and there's not much you can hide from him. And when you're eloped in his ice, he protects you until he breaks.
This, is why Cho and Rigsby are such good partners. They protect each other, their weakness is the others strength. Rigsby's fire is strong enough to melt the ice, while Cho's ice is enough to weaken the heat of Rigbsy's flame. And when one begins to burn more than the other, the other steps it up.
Lisbon knew what she was doing when she put the two very opposite people together. Even their motives were opposite on joining the CBI. One joined because he was a criminal that wanted to redeem himself. He wanted to show that there are other ways to live except being in a gang. The other joined because his father was a criminal, and he wanted to put parents like that away so that they will not hurt their children again.
Both motives are simple and complex all at once. No one knows the full story of their past, no one knows what extremes they lived in. No one except each other.. Not that they told each other their past, the other just knew. Because they are partners, and that's what partners do.