Percy was absolutely stunned.
He believed he was probably about to die, right there next to the lava. He had made peace with it.
Sure, he was going to fight the hell out of those damned creatures and try to return to his friends, but when he told Annabeth to leave, he knew.
Percy knew he might die.
Annabeth knew it too, and for a moment, she refused to leave. Percy, though, pushed her to see she needed to warm Hephaestus and let him know what was going on.
He did it using the only thing he knew she couldn't fight against: Reason.
If they both died there, everything would be lost.
He as also certain she was going to punch him... and hard. But she didn't.
She did the complete opposite: Annabeth kissed him.
It was a quick, yet passionate and perfect kiss and Percy had never felt so lost and so happy in his life, all at the same time.
He couldn't breathe, as if he had forgotten how to inhale and exhale.
In fact, he had forgotten his own name. He had forgotten about anything and everything, except her name, and that perfect kiss.
"Annabeth..." He mumbled, but by then she had already vanished.
Now he knew he couldn't die. He needed to kiss her again.