It was no secret that Obito had always been jealous of Kakashi. Since the Academy Obito had been jealous of his strength, his genius, his early graduation...the feelings Rin had for him.
He was jealous of how Rin and Kakashi grew closer after his 'death', how Kakashi was the last person she looked at, how it was his name that was the last word on her lips.
Obito let a small, bitter smile stretch his lips ever so slightly.
Now he was jealous of Kakashis obvious closeness to the Kyuubi jinshuuriki. The whole time they were fighting Naruto showed that he obviously cared about Kakashi while the man could only concentrate on Obito. Really, Kakashi should show some appreciation for the sole reason he was still alive.
Obito wished he had someone like Naruto. Someone he could trust not to stab him in the back. Someone that would have his back even when he was his lowest. Someone who had unshakable faith in him.
That train of thought only lead him to more anger. How dare he? Kakashi always had what Obito wished for the most and he dared to demand MORE?!
Damn. Now he really wanted to stomb Kakashis face into the ground.