Blorbos from my books, I missed this scene not being in the anime.
:) I love them.

Spoilers from Goliath below:

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“Stay awake!” Deryn cried. “Talk to me!”

He searched for words, but the rain seemed to strip away his thoughts before they could form. Staring at Deryn, Alek felt his mind switch back and forth, seeing her as a girl, then as a boy. And he realized what he had to say.

“Promise you won’t ever lie to me again.”

She rolled her eyes.

“I mean it!” he shouted above the wind. “You have to swear it, or we can’t be friends.”

Deryn stared hard at him another moment, then nodded. “Aleksandar of Hohenberg, I promise never to lie to you again.”

-Excerpt From Goliath Scott Westerfeld