Severus Snape didn’t fall in love.

It was one of the salient facts about him.

All right, he’d done it once before, and though it helped save the Wizarding World, it had been something of a personal disaster for him. And for the object of his affection.

Which was why he was utterly gobsmacked to recognise, in the year of no Dark Lord 2010, that he had, in fact, done just that.

This startling event happened twelve years after he’d left Hogwarts for good, or so he’d believed. Twelve years of (relative) peace and quiet; twelve years of respite from teenaged dunderheads (there remained plenty of the older variety in his life, he was sorry to say); twelve years of living blissfully (or what passed for bliss in Snape’s world) alone.

It all started one day — well, really it had started long before, but all that backstory would make this tale far too long — it all started one day when he was sitting in the lab at the back of his Walthamstow flat (you didn’t think he’d gone back to Spinner’s End, did you?) He was considering whether he should finish the batch of Wideye Potion he’d been brewing or put it under a Stasis Charm and hit the local for a pint and a bacon butty.

Fuck it, he’d go down the pub. His customer could wait another few hours for her potion. Her internship at St Mungo’s wouldn’t even start for another two days, and, Severus told himself, she ought to get a head start on some sleep in the meantime.

Severus had just doused the flame and set the charm when a post owl pecked at the tiny back window.

The bird hooted in annoyance when it couldn’t fit all the way in and had to settle for exchanging its parcel for an owl treat though the small opening.

What kind of moron uses an enormous snowy owl to send a letter-sized parcel, anyway? Severus thought as he broke the envelope’s seal.

(His correspondent was no kind of a moron at all. You needed a robust sort of owl to fly all the way from that northern hellhole, as Severus tended to think of Hogwarts, to London in February weather.)

He glanced down at the signature and slightly revised his estimation of its sender.

Severus sighed. He supposed he’d actually have to read the letter. It would be bad form to ignore a communiqué from the headmistress of Hogwarts, even if he had nothing to do with the place anymore. (Not that good form was anything he cared much about. But still.)

He had to scan the thing twice to make sure he wasn’t hallucinating.

Unbefuckinglievable.

She was actually asking him to come and teach.