Cas misses tasting things. He misses PB&J, burritos, coffee, whip cream and even the minty taste of toothpaste. Everything tastes like chemicals and molecules now, boring and uninteresting.
So when Dean comes up to him in the hallway between their rooms, pressing Cas against the wall and kissing him for the first time, Cas is startled. Not from Dean kissing him but because, Dean doesn’t taste like molecules.
He tastes like stardust and lightening, mingled with humanity and coffee. It’s a strange mix of flavors but blended together are a perfect combination.
Dean somehow turns out to be the most delicious flavor Cas has ever tasted.