Channing Ngo was Kevin Tran's girlfriend.
Channing was first seen talking to Kevin about an upcoming test, taking place shortly before the tablet inscribed with The Word of God was broken open by Sam and Dean. Later, when Kevin was driving his mom's car, Channing called him to rant about how he missed school, a student council-meeting, and the test they had previously discussed. He told her that he had been chosen - but he doesn't know what for.
In an effort to find Kevin, Sam and Dean talked to his girlfriend. Channing told them that she does not know where Kevin is and informed them that she broke up with him. She justified this by stating "when he was going to Princeton University". It later turns out that she was possessed by a demon, who, after murdering a fellow student for her blood to make a call to Crowley, revealed to him that the Winchester brothers were looking for Kevin. When Crowley and the demon-possessed Channing found Kevin and the Winchesters, Kevin agreed to go with Crowley under the condition that the demon be released from her.
Crowley agreed, and to prove that the real Channing is still alive, he ordered the demon to temporarily release control. The real Channing was delighted to see Kevin, revealing that the "break-up" was the demon's words, but the demon quickly got its hold on her once more. Kevin tricked Crowley and the demon by drenching them with holy water. Dean, Sam and Kevin quickly fled. Crowley ordered the demon possessing her to find a new meatsuit, prompting it to leave Channing's body. It is then and there that Kevin witnessed Crowley snapping her neck, killing her.