Because Maya's already lived through losing everything important to her at one point or another. In the face of that, Derek's just a grumpy asshole who needs to lighten up.

She sighs, the sound clearly exasperated even as a cat. Her tail swishes a little more intently before she bumps her head against his hand. She doesn't stop there though, licking a raspy stripe over his fingers.

That's a 'no'.