She hadn't even meant to find the recipe—she had been looking through the tome to find a spell that would magically seal a piece of parchment to save it from water damage. But, there it was—the answer to all her problems.
Severus was the hardest person to buy presents for. He was never any help—whenever asked, he would shrug and just tell her to get whatever she thought would make him happy.
So, she'd gotten him potions ingredients and parchment. One year, she'd even knitted him socks, but he'd only used them to polish his potions equipment. The socks had been Dumbledore's portrait's idea—she had mentioned this to Harry, and he'd just laughed and mumbled something about the Mirror of Erised.
Therefore, when she found the recipe, she knew she had struck gold. The brew only took two hours to make, so she'd have plenty of time in the week remaining before his birthday to create it.
Severus looked at her, curiosity arching his left eyebrow. She sat perched on the corner of his desk, looking down at him expectantly. The box was small and could have held something as innocuous as a ring or cuff links… or a bezoar. He made a point to slowly remove the ribbon and to open the paper without ripping it, knowing it irritated her.
"Dammit, Severus, just open it!"
He ripped the paper off, tossed it aside, and finally opened the small box to find a small, glass bottle nestled inside of a bed of cotton. In it was a viscous, red liquid held in by a black stopper.
Severus was confused. "Blood? You got me blood, Hermione?"
Hermione grinned. "No, I made you ink! Blood-red ink that retains its freshly spilt shimmer on parchment. I thought it would be most appropriately used to scare first-years," she said, mischievously.
Severus was dumbfounded. It was the only perfectly conceived gift anyone had ever given him. No one had ever given him something so thoughtful. He quickly moved to his desk, pulling a first-year essay out of a drawer. He uncorked the bottle and dipped in the quill. Smirking, he began to write across the parchment, lambasting the poor student for grammatical and factual errors.
He hadn't seen this much gore since his last Revel.
His face split into a crooked grin, showing off just how twisted his incisors were. He conjured a length of leather and bound his hair at the nape of his neck. He put on his black-framed reading glasses and looked up over them at her.
"My dear, I do believe I have some marking to do. Dinner reservation is in an hour, yes?"
She nodded and walked out of his study. He had never seemed that happy to grade, and she felt she'd made the right choice.
The cackle she heard emanate from his study ten minutes later confirmed her feelings.