Some of us are speculating if kurama will betray Naruto...!
The answer is mostly no. The reason being when Naruto tagged with Goku and then with Kurama he felt the same warmth or affinity in both of them. Thats why Goku says "It will help you out" to Naruto after joining fists with him. Also Naruto expression suggest that he felt the same thing when he joined fist with kurama thats why he released Kurama. Also kurama is not sneaking at Naruto ... look at his eyes not looking at Naruto but some one front of him... Tobi is my guess!!