Congratulations, Matthew and girlfriend! I could never be with someone who was not at least open-minded about it. I married my best friend. Communication is of the utmost importance. Here's something that we discovered - even definitions can be different. Talk about everything and make sure you are both on the same page. Happy for you. Enjoy the hell out of each other!
Congrats from me as well. May you both be kinky happy, preferably ever after.