The five men who raped Freya, Void's or Pablo's sister, were from the military and if Pablo wanted his body to not flinch often, he needed to kill those five men. And to kill them, he needed to join the military.
Pablo hadn't told many people that he wanted to join the military. The only time he told this to a stranger was when the man in the booth asked him about his career preference.
So it would be a lie if Pablo said he wasn't surprised when the daughter of the Count offered him her help in joining the military.
But Pablo didn't show any of his shock on his face. The girl could be testing him. It was possible that she was just throwing an arrow in the dark, not really knowing for sure that Pablo indeed wanted to join the military.
So, Pablo tested her in return as well.
"Why will I ever want to join the military, my lady? And I am too lowly for you to talk. It will dampen your status if you are seen with me." Pablo acted humble.