Unlike most demons, you actually seemed good, if that was possible. Sure, Sam had his doubts about you at first, considering how terrible Ruby had gone. But you were different, and it seemed good for Sam.

However, Sam doesn't want you going with him to meet up with Dean and Cas for this hunt. Cas doesn't exactly like you and has been a bit 'trigger-happy' when it came to demons. Neither Dean nor Cas trusted demons so Sam saw it as the best thing... to trap you in a devils-trap.... But just till