Learning To Love
Tom Riddle had long given up on finding his soulmate. The sappy tales of two halves of the same soul finding each other were just that: tales. And even if they weren’t, the mere thought of him having a mate was ridiculous. How could anyone be a match for him, the most brilliant student Hogwarts had ever seen? How could anyone rouse affection in him, when nothing had done so in his the fifteen years he had lived?
And yet, in the beginning of his fifth year, he ends up in a soulmate dream and feels for the first time. It’s addictive and it’s incomparable to anything he has ever felt before, and even if he tries to resist it, he knows there is no way to win this one.
So he does something unimaginable, something he could not have imagined just a few weeks prior.
He decides to give love a chance.
Or:
On the night the werewolf attacks him, young Severus Snape dies and somehow, wakes up in 1943. After a very exhausting interrogation in the Department Of Mysteries, he is eventually given a temporary guardian and the permission to continue his education in Hogwarts. (Because, as Headmaster Dippet put it, he is a child first and foremost and a time traveller second.)
It doesn’t take long for Severus to notice that this Hogwarts has only surface-lever similarities to the school he had gone for four years. The politics in Slytherin are weirdly unfamiliar to him, and the customs and ways the House operate are almost unrecognisable. The uniforms are foreign, too, and the library… it’s full of books about dark magic.
Above all, however, is the fact that he has a soulmate here. A boy his age, a brilliant wizard called Tom Riddle. He’s everything Severus is not, popular, good-looking and classy, and yet he still wants Severus.
For once, Severus Snape is happy – even euphoric. But he knows fully well that good things never last, that they are fragile and easily broken. And so, when he hears a tiny voice in the back of his head, he cannot help but listen to it.
If he had had a soulmate all this time, why didn’t their soul bond activate in 1975?
Or:
A yet-to-be Dark Lord meets a young time traveller called Severus Snape and falls in love.
Nevermind that his beloved is trying to return to the future.