Castiel was at his last nerve with Metatron. You, him and the aforementioned angel were in the car, Metatron upfront, you at the back. And he just wouldn't shut up.

"Watch it," Castiel muttered to him, glancing back at you as you had to endure Metatron flirting with you. It pissed Cass off to no end.*

"Oh, come on, asstiel, they like it!" Metatron chimed in that annoying voice he posessed.

One look at you told Cass you did, in fact, not like it, so he spoke. "Leave them alone."