#Naruto ch584: I grow tired of Kishimoto's predictable exposition, but I love seeing Orochimaru again. #manga 

Given what I know now, it's easy to see how Kabuto was able to fall
under Orochimaru's sway. It wasn't a bad deal. He got some of the
answers that he wanted, and the opportunity to what he did not have.
And in Orochimaru's flight from Konohagakure, he was protected from
Danzo and Root. It was all a very natural fit. Too bad he'll never
be sated.