Of Lilies and Smoke | Harry Potter AU

There was a time when Lily Evans and Severa Snape had no secrets from one another.
Two children from the same grey mill town, they discovered magic side by side-testing spells by the riverbank, filling jars with wildflower brews and calling them potions.
At Hogwarts they promised nothing would ever come between them.

But promises are fragile things.

By their sixth year the distance between Gryffindor and Slytherin has widened into a gulf neither dares to cross. Lily has become the pride of her House-bright, admired, endlessly kind-while Severa has drawn inward, burying herself in study and shadows. One evening, when feeling began to outgrow friendship, fear took its place. Severa vanished behind silence, and Lily was left with nothing but questions.

Now Professor Slughorn has announced a competition for the coveted Slughorn Medal: a month-long partnership to create a potion worthy of publication.
To their mutual dismay, the two best students are paired together.

In the quiet of the dungeon laboratory, amid candle smoke and the scent of crushed petals, the girls must work as one-measuring, stirring, pretending not to remember what they've lost. Old affection flickers beneath every clipped word and accidental touch, and Severa finds that the harder she tries to master her craft, the less she can master her heart.

As rumours of darkness spread beyond the castle walls, their cauldron yields more than vapour and colour; it reveals what happens when warmth meets control, when loyalty tests love, and when a single unspoken truth can change the course of two lives.

Some potions transform the drinker.
Others transform the maker