Jax was anything but vulnerable.
He was sarcastic, chaotic, reckless. He didn't need help, he didn't need anyone to like him. He didn't ask, and he didn't care.
At least, that's what he convinced himself of.
When you came along, he didn't mind. Not at first. You were just another face, a new character that would grow to dislike his brash personality just like the others, someone who would take him at face value and walk away. That's what they all did.
So when you checked up on him even after troubling adventures, noticed when he wasn't okay, cared about what he said, it confused him. You were supposed to leave him be, not worm your way into his life.
Even as he sat beside you during the stargazing adventure, ranting about Ragatha, he couldn't help but think — why you?