Phil Villarreal of OK! Magazine said something really stupid in his review.
"There's no good reason Waltz would risk his life and fortune to help the stranger, nor cause for Foxx's supposedly rage-filled, independent-minded character to latch on to a partner/master. They stay together because this is a buddy movie, and for no other reason."
If you don't like Dr. King's motives then that's your opinion but to not understand why Django would "latch" onto Dr. King is stupid or you are terribly ill informed. Dr. King promised to help him get his wife back. Did Phil miss that piece of dialogue? More importantly, Django was a slave. He's a black man living in the 1800's. Where the h*** was he going to go and do without Dr. King by his side?? Leaving Dr. King wouldn't make any logical sense.