Castiel bit his lip, and concentrated even harder. He had the small brush in his right hand, and he carefully swiped it over a nail on his left hand, the brush smearing a bright, glittery blue over the nail. He frowned when he saw that some of the polish had spread to the area around the nail, but he decided to clean it up later.
Castiel reached in front of him and dipped the brush into the small blue bottle, and then started on the next nail.
He continued painting his nails, finishing the nails on his left hand and then waiting for them to dry, and then began on the right hand. He found it much harder to paint his nails with his left hand.
Castiel heard the sound of the door opening, but he didn't bother to look up. He was currently sitting on a bed in Sam and Dean's motel room, so he knew it was just one or both of the brothers.
"What the hell?" Dean's voice startled Castiel, and he jumped. He managed to grab the bottle of nail polish before it tipped over.
"Dean, you almost made me spill it," he said, frowning. He looked up to Dean, who was giving him a puzzled look.
"What are you doing?" he asked.
"I'm painting my nails. I thought that was obvious." Castiel then held up his hand, showing off his shimmery blue nails. He then set down the bottle of nail polish, and continued his painting.
"But isn't that kind of a... girly thing to do?"
Castiel tilted his head slightly to the side, but didn't bother looking up.
"I have no sex. Technically, my vessel is male, so I suppose that makes me male, but in my angel form I didn't have a gender. Also, I have seen males with nail polish."
"But-"
"In Heaven, my angel form had talons. Sometimes I'd paint them black, or gold for special occasions. So this kind of reminds me of that. I like painting my nails," Castiel said.
Dean decided to just drop the subject. He moved further into the room, heading for the bathroom.
"At least you chose blue. It matches your eyes," he commented dryly.
Castiel merely smiled and continued painting.