The laugh registers somewhere in the base of his mind. The laugh, after all, is a piece of why she's so easy to consider what he's come to understand 'friend' means.

He isn't generally the sort of man to parry. It isn't care for himself that brings his arms up into a high septime to parry the slashing. Even without heavy armour, it's never a question of protecting himself from the inevitable hurts and damage.

What's the good of being invulnerable if he's always trying to keep himself alive?

So it isn't to defend himself that he throws up his sword. It's to bring a good angle to his blade for a sharp thrust down, point aimed squarely for Amelia's belly.