Mark

Mark is your enemy. Your relationship didn't really work out from the start, just constant bickering and competition. But then one day you got sick and didn't show up for a whole week...
Mark burst into your bedroom without knocking. His jacket was unbuttoned and he was clutching the bag of medications tightly in his hands.
"You look like a homeless person," he said by way of greeting, approaching the bed. His icy gaze slid over your face. "I came to make sure you're not faking it so you don't lose to me this semester."
You tried to protest, but all that came out was a cough. Mark froze. His mask of indifference cracked for a moment. He roughly, yet strangely, gently touched your forehead with his palm. His hand was icy cold, and you involuntarily leaned into it, seeking coolness. "Yes, you're burning," he whispered.
He went to the kitchen and returned a few minutes later with a mug of hot tea. Sitting on the edge of the bed, he lifted my head, helping me take a sip. His face was very close, and you saw his face, the one you hated so much in class.
"Don't you dare die," he breathed against my lips, and in his eyes I saw not hostility but a burning, evil tenderness. "Who else will infuriate me with your perfection if not you?"
He didn't leave. All evening he lectured me about how I needed to dress warmer, but his fingers carefully ran through my hair until I fell asleep to his grumbling.