Desperate Passion
Derek grabs him and pushes him up against the wall, so hard he can feel the outline of the bricks pressed into his back.
"Why do you care so much?" Derek growls, and to Stiles' shock he can see the hint of tears in his eyes.
"Why do you care what happens to me? Why do you keep helping me, saving me?"
With these words something clicks in Stiles' head.
"Because I love you." he murmurs, and with these words he presses his lips to Derek's.
It's tentative at first, just a brush, and Stiles feels drop somewhere to the vicinity of his ankles. But then Derek presses back, harder and more firmly, pulling him away from the wall and wrapping his arms around him. Their mouths open and Stiles threads his hands through Derek's hair, pulling him closer. Soon, they're locked together in a sort of desperate passion, striving to put as little space between them as possible.
And then they break apart and Derek just collapses against him, as poorly suppressed sobs cause his shoulders to shake against Stiles' chest.
"You shouldn't love me. You shouldn't give a fuck about me." Derek chokes out, and all Stiles can do is pull him closer, and murmur in his ear,
"But I do."