The potion was delicate. He'd made it a few times before, each with the same perfect result. It required him to be completely focused on the cauldron, on the ingredients, and on the incantation that he repeated in his head every time he stirred the ever changing mixture. He dropped three dried fig leaves into the silver liquid, stirred it twice counterclockwise and was satisfied when it turned a vibrant yellow color.
'Severus, I need your help with something.'
The voice caught him off guard – he'd been so focused on the potion that he hadn't heard Auriga come into his lab – and he dropped the spoon into the potion.
Not good.
He waited for the explosion, closed his eyes tightly and waited for the stone shattering boom.
Nothing.
He opened his eyes to find Auriga looking at him strangely. 'Something the matter?' she asked.
'Auriga, what have I told you about knocking before coming here?' he said with a deadly quiet voice. He stared at the potion with a dumfounded expression. It was still yellow.
'I know, but I forgot. Besides, you're working on the medicinal potions today, nothing volatile.'
The timing was perfect, so perfect that if asked later he'd have to commend the gods for having such a perfectly balanced sense of humor.
Auriga smiled innocently at him, the potion turned purple, and the cauldron exploded, covering both of them – and most of the lab – in a sticky purple mess.
He calmly wiped potion from his eyes and stared at Auriga with a look of murderous intent. She smiled back at him.
'Purple is a lovely compliment to your pale skin, Severus,' she said.
To his credit, he didn't mean for the glob of potion stuck to his hand to smack her in the forehead but when it did, he felt a certain sense of satisfaction.