Kid and Luffy are playing off each other in the best of ways. For one, Kid is finally able to show off his true strength in the jail now that Luffy is there to push him In the beginning of the alliance Law made it clear it was just an alliance, but we all know to Luffy it meant something totally different. I love how Law just strung along with Luffy and went with everything he told him to do. Law might not admit it but I feel like he really enjoyed his time with the straw hats.