"How do you do it?"

Snape was currently concentrating on adding crushed butterfly wings to some kind of rose-coloured potion. He didn't even look up at the question, but he halted his movements for a second, indicating he'd heard it. 

Harry was seated on a stool far enough from the other man‘s work bench to not be the cause of a failed potion. When Snape had restricted him to that particular part of furniture, Harry had complained, saying that his bad potion skills were hardly contaminous and that besides, he wouldn‘t even touch the ingredients or the cauldron. But Snape had insisted (and everyone knew it was best to obey when Snape told them to do something). The Potions Master had muttered under his breath "I'll be damned if I ever let a Potter tell me what to do." Harry had barely able to bite back the retort that he wasn‘t a Potter anymore, since the official papers had been signed only a few hours before and that Snape did in fact indulge him now and then.

"Do what, boy?" Snape answered impatiently.

Harry swung his legs back and forth, careful not to hit the stool with his sneakers though because he knew Snape hated that habit of his.

"Making your robes billow behind you like that. I've wondered for a while, you know. Is it a spell? Or did you practise?"

Snape threw him an incredulous look over his shoulder. "That is positively the most inane question ever asked. And kindly do stop that infernal swinging and dangling."

Harry did, but couldn‘t stop himself from pouting. "It was a perfectly normal question," he answered grumpily.

Snape added a last ingredient to his brew (Harry didn't pay attention on what it was, he couldn‘t care less about potions and he was still quite busy pouting) and turned around. Crossing his arms, he leaned against the workbench behind him and studied the boy before him. 

"Stop pouting," he admonished. "You are not five years old."

"I'm not pouting!"

Snape frowned. "You are. And you are wasting my time."

"Am not!" 

"Harry Snape! You are acting like a toddler. Would you like a bib and a diaper?"

Harry's head shot up with the speed of lightning. "You wouldn‘t!"

He couldn't keep himself from shuddering as he saw the smirk growing on Snape's face. 

"Try me," he said dryly, his tone of voice not betraying the amusement Harry saw dancing in his guardian‘s eyes. 

He straightened and tried looking adult-like. When he saw Snape's lip twitching he sighed. 

"Fine Dad, you won."

Snape raised one eyebrow. "Of course I did. It would do well for you to remember that I always do."

Snape started clearing away the ingredients he had been using in his potion and bottling the mysterious connoction. 

"Should've asked someone else to adopt me," Harry murmured darkly and jumped down from his stool. Snape didn‘t pay him any mind, but Harry knew he had heard his comment, for after a few minutes Snape turned to look at him, still smirking. 

"I'm afraid now it is too late for remorse. The following years will teach you to think before you act."

Harry rolled his eyes at his teacher's back. "Only you would manage to make an adoption into a lesson for life."

Severus Snape was making his way towards the door. "It is never too late to learn. Now are you coming or am I supposed to eat that incognisable mountain of whatever you may call it all by myself?"

Harry scowled, but hurried after his guardian. "It‘s pasta. And it's not that bad."

Then he remembered something and his head perked up again. "And you still have to tell me how you do that robe-thing! Is it practise or a spell?"

Snape snorted. "Neither nor, Mr. Snape. It is purely a useful skill, by the way one of those that you never will be able to aquire."

Now it was Harry's turn to snort. 

"Hardly can be that difficult to let something billow a bit, can it?"

Snape suddenly turned around and Harry almost crashed into him. Black eyes met green ones and the Potion Master's face became very, very serious. 

"Do not underestimate the art, Harry Snape. It is not an easy one to archieve."

He then strode further down the corridor, leaving his adopted son to his musings. As Harry took up his steps he pondered that Snape probably really had practised this for quite a while. 

Well, he had always been rather dramatic.