Huynh was sentenced Wednesday to 26 years to life in prison at Los Angeles County Superior Court in Long Beach.
"I don't think it was in the heat of passion of the breakup," Klein said. "It seemed to me based on everything he did before and after (the killing). He'd made up his mind, he was never going to let her break up with him."
The pair were alone in her room when Yi told Huynh she was breaking up with him. Using her belt, Huynh strangled her, stuffed her panties in her mouth and shoved her body into a small bedroom closet.
Yi's body would remain there for two days until her roommate discovered it while looking for clues to her whereabouts. The woman ran out of the room screaming and called Yi's parents. The couple had to pull their daughter's body out of the closet because it was so tightly lodged in there.
After killing her, Huynh used Yi's cell phone to call the roommate, telling her that Yi had left the apartment angry and he couldn't find her.
Prosecutors said that in the days following the killing Huynh went about his life as if nothing had happened, posting things on Facebook, shopping and playing computer games at The Block in Orange. In fact, he was arrested there the day after the body was found.
At one point during the trial Huynh testified in his own defense. Klein said that he laughed on the stand, and media reported that he giggled and smiled during his sentencing.
"I think he shed some tears," Klein said. "The tears seemed to be primarly because he was sad he got caught."