One day Stiles was just there, in front of his house.
Of course Derek had heard him coming miles away - could pick out the sound of that stupid blue jeep from anywhere. What Stiles was doing, however, was decidedly not something Derek could have seen coming. In fact, he’s so taken by surprise that during Stiles’ entire visit to the Hale house, Derek doesn’t say a single word.
It goes something like this: Stiles parks his car right outside the house, steps out and walks up to (what’s left of) the door. Since Stiles is now considered pack and Derek is (no matter what people say about Scott) the Alpha, he grudgingly meets him there.
Stiles speaks before Derek has the chance.
“Look. I know this is a little out of the blue, but I have thought this through, I’m not an idiot and well... here.”
And then he thrusts a fucking silver jewelry box into Derek’s hands. It stings. Derek would have dropped it if it weren’t for Stiles’ hands still holding onto the box and it irks Derek how easy he is for Stiles to read.
“Go on, open it.”
And suddenly Derek has entered the twilight zone for sure because in the silver jewelry box is, what he can only assume, Stiles’ heart.
Stiles’ hands touch Derek’s, making sure the other man doesn’t drop the box, before calmly walking back to his jeep, getting in, and driving away. As if the world hadn’t just tilted off its axis.
Derek doesn’t know how long he stands there staring down at the beating heart, but by the time he finally retreats back into the house the sting has developed into a burn.
He puts down the open box on his sooty kitchen table and it looks so out of place that Derek just wants to shut it and throw it out.
He takes a seat in front of it on a rickety chair that might actually fall apart any second and just... stares.
The showing of hearts is very intimate.
Before this he’d only seen his family’s hearts; even then it was only those who were really close to him and he’d only seen glimpses, if that.
You keep your heart close to you, but preferably out of sight.
The jewelry box, judging by the tiny inscription on the lid, had belonged to Stiles’ mother. Just that fact is enough to make his skin crawl. Stiles could have at least kept the box... then, of course, the heart inside of it was maybe a bit more important.
It’s a healthy heart; beats strongly even without Stiles there to anchor it.
And that’s when it truly hits him.
Stiles trusts Derek with his heart.
He snaps the lid shut, takes the box and shoves it into one of the kitchen cabinets.
The day after, Derek goes to the hardware store. He buys everything they have that could possibly be needed to restore his house and what they don’t have, he orders.
He works for hours and hours; works until he can’t see straight and he starts making mistakes that he’ll have to fix in the morning, but before going to bed he opens the kitchen cabinet to take out the silver box, only shit, apparently he’d cut himself without noticing because there’s blood on his hand.
He washes his hands carefully, feeling layers of blood and grime and sweat peel off. He scrubs them until his hands at least are as clean as they can be before returning to the box.
He opens it and there it is, just as he’d feared - a tiny crack running straight down the middle, blood pooling inside of it.
He’s only had Stiles’ heart for a day and he’s already breaking it.
He shuts the lid, returns it to the cupboard and goes to bed.
It becomes routine. Every night after tearing down and building again, he looks at the heart. Over the weeks it’s become a bit smaller, and it doesn’t appear to be quite as colorful as it was.
Derek is at a loss.
One night he sleeps with the box next to him, and when he wakes up, if Derek’s eyes don’t deceive him (which they very well could be), it looks just a bit healthier.
He buys a new nightstand and every night, he puts the silver box on top of it.
It’s not like they don’t see each other, they see each other plenty. Between the increasing number of pack meetings and the alarmingly increasing need for research because Beacon Hills is apparently the flavor of the month - scratch that, year - now, they see more of each other now than they did before.
Derek keeps waiting for that moment when Stiles will stay behind after a pack meeting, or when he’ll say “before I google-fu this bastard, we need to talk…”
Derek keeps waiting for that moment when Stiles will admit that he made a mistake, but it never comes.
Stiles never asks for his heart back.
Derek doesn’t offer it.
When he’s finally finished rebuilding the old Hale house, he allows himself something he hasn’t since Laura’s death.
He takes a shovel and enters what used to be the garden. He lets himself be guided by the weak pull, and when he’s at the right spot, starts digging until the shovel hits metal.
The can of peas is rusty and smells disgusting to Derek’s heightened senses as he pries open the lid and shakes out the heart inside.
Where it isn’t dirty, he can see that it’s a sickly shade of grey and it beats weakly in his hand. There are scars all over it, some old and some new.
When he’d left it there after Laura’s death it had been with clean, precise cuts all over it, gushing blood all over the place.
It looks so much better now than it did then.
He tells the others not to come for the next pack meeting.
Stiles shows up, confused, asking why Scott suddenly decided he was too good for his Jeep.
They’re standing where they were when Stiles gave Derek his heart and while Derek isn’t a romantic, he can appreciate this. He can appreciate the look of confusion on Stiles’ face as he gets handed a cleaned up can of peas.