Becca was an angel of the Lord living on Earth for thousands of years, guarding humans who deserved it from time to time, but hiding for the most part of it. She hadn't be in heaven in thousands of years, afraid of them to know the truth about her feelings towards her own brother.

Against every odd, against every implied rule, Becca was in love with Castiel, her angelic brother, ever since she was decades old, learning her duties with him in heaven. For centuries she hid her feelings from him under his nose, but a time came when she couldn't look at him and not desire him anymore, so she ran away.

Thousands of years later, the angel was hiding among humans when she lost her grace and encountered him again. Now, Becca was in the bunker, living with the Winchesters and Castiel, saving the world from monsters and demons and deceiving her feelings once again.

"Becca?" She heard Dean's voice.

Silently, she appeared in the room with a flap of wings, surprising the Winchester.

You could have just walked here" He stated. "You angels…"

The redhaired angel ignored his complains.

"Is my assistance needed?"

"Sam nodded quickly, showing her a book.

"Do you know anything about this symbol?"
When she leaned down, Sam's hand touched her wrist softly, and the female angel felt Cass' eyes lading where their skins touched each other's.

"It looks Hindu." She decided after a long look, and used her grace to bring a pair of books she knew could help to the table. "Here. Those books may have an answer."

She sat by his side, grabbing one of them and opening it.

Castiel watched as Becca read beside the younger Winchester. Sam was always showing affection towards her, and the male angel didn't feel good about. There was something about him touching his sister that made him bothered and angry, but he didn't want to think about the reason.

"Am I the only one seeing it?" Dean called his attention.

"It?"

"Dean rolled his eyes.

"My brother and your sister." He pointed. "They are a match."

Castiel frowned.

"No, they're not." He spat back, standing up and leaving the three alone in the map room.

A small amount of angels had relationships with other angels. Once, that was a taboo, but centuries after she left heaven it had slowly become normal. But it didn't change the fact that he was ashamed of his feelings for her; not because they were wrong, but because he thought his sister would never see him like more than just another brother.

See her with Sam… It was painful. It made him want to take Becca in his arms and fly away so they could be alone together.

"Castiel?" He heard for a moment inside his head. "Is there any problem? You looked disturbed."

"No, sister." He lied. "I'm just intrigued by the hunt."

"She stood in silence for a long moment before answering.

"Do you trust me, brother?"

Castiel was surprised by the question.

"With my life." He didn't hesitate.

Becca's next words and the sad tone in her voice echoed painfully inside him.

"Then why do lie to me?"

To that, he had no answer.