Ten years later

Albus Dumbledore sat on his desk, waiting. It didn't usually take Severus that long to come to his office when ordered to. Without knocking, the potions master entered the office as if it was his. He carried the pensieve which obviously held a feather light charm. Snape's face expression was ice cold and furious.

"You can have it back, Professor," he hissed and was about to leave the room again.

Albus raised his hand. "Wait, Severus."

After a moment of hesitation, Snape turned around, glaring at Dumbledore.

"Wait. You cannot stop Harry's lessons. I will not allow it."

Snape's face turned into an ugly grimace.

"I don't care. I refuse to teach him occlumency any longer. In fact, I refuse to teach him potions, too. I will dismiss him from my class."

Albus was surprised. It wasn't often that Severus was that angry and distressed.

"What happened Severus?"

The potions professor stood up, again, ready to go. Now Albus stood up, too.

"Severus. If you don't even tell me, I am unable to understand. You have no right to disobey me, you gave me your word. I trust you Severus and if you break that trust I will have to sack you. You will not survive a week out there without my protection."

Severus nodded slowly, tears of anger in his now bright red face.

"I see professor. You are blackmailing me to teach that insolent little..."

Dumbledore raised his hand to tell him to stop.

"Professor," he continued, "You gave me your pensieve to protect my privacy and Potter broke in! I cannot continue now."

Dumbledore sat back down. His eyes were full of disappointment.

"Severus, sometimes I am amazed that I even appointed you as a teacher. Think Severus, just THINK! Potter would not dare to break into your memories if he wasn't somehow guided by Voldemort. Mine, maybe. But not yours. He has escapades where he cannot control himself. It is not possession. Not the same thing that happened to Ginny Weasley. It is far far more complicated than that and you are the only one who can teach him to stop it."

"But Professor," Snape interrupted, "when he broke into the pensieve he saw..."

Snape wasn't able to finish the sentence when Dumbledore again, stood up, now raw anger in his face. It was not often that he lost control to that degree.

"Professor Snape. That boy just had to witness that his father was not the kind of person he wanted him to be - the kind of person Harry is - And YOU are thinking about yourself? Do you have ANY idea how serious this could be? You are continueing. I will hear NO more complaints from you. You will teach him occlumency until he masters it. Dismissed."

Snape seemed to have shrunk a little.

"Dumbledore, I am not sure if he is actually able to learn. He seems unable to occlude his mind. His intelligence doesn't seem..."

Dumbledore shook his head and very quietly whispered: "Then you will find out why he is unable. Get started."