Jace and Clary from 'The Mortal Instruments' by Cassandra Clare.
Spoiler alert for 'City of Glass'!
"I told you I couldn't sleep. Tomorrow by midnight we'll be either at war or under Valentine's rule. This could be the last night of our lives, certainly the last even barely ordinary one. The last night we go to sleep and get up just as we always have. And all I could think of was that I wanted to spend it with you."
Her heart skipped a beat. "Jace-"
"I don't mean it like that," he said. "I won't touch you, not if you don't want me to. I know it's wrong –god, it's all kinds of wrong –but I just want to lie down with you and wake up with you, just once, just once ever in my life." There was desperation in his voice. "It's just this one night. In the grand scheme of things, how much can one night matter?"
Because think how we'll feel in the morning. Think how much worse it will be pretending that we don't mean anything to each other in front of everyone else after we've spent the night together, even if all we do is sleep. It's like having just a little bit of drug –it only makes you want more.
But that was why he had told her what he had, she realized.
Because it wasn't true, not for him; there was nothing that could make it worse, just as there was nothing that could make it better. What he felt was as final as a life sentence, and could she really say it was so different for her? And even if she hoped it might be, even if she hoped she might someday be persuaded by time or reason or gradual attrition not to feel this way anymore, it didn't matter. There was nothing she had ever wanted in her life more than she wanted this night with Jace.
"Close the curtains, then, before you come to bed," she said. "I can't sleep with this much light in the room."
-City of Glass, page 304, by Cassandra Clare.