8D
[She's calm about it, though she takes a deep breath as he bites down because of the pressure rather than the pain. Able to use her own cells to synthesize zippers and all sorts of metal-like objects, making her skin something durable enough to take on a bite is easy enough. The skin's resistant and refuses to be broken even by the sharpness of his fangs, so she wraps her arms around his neck and kisses it soundly.] Mmh, told you.
[Bite harder if you want, but if you're otherwise satisfied, she'll return her hand between them to unzip those pants.]