"Ahaha, she's just shocked at the size of your thing...don't worry, she signed up for this, we all did. Every full-time rancher here is a horse girl, that's just part of the commitment you make to the family when working here. It's also helpful for practical reasons, gets you closer with the horses, helps you vibe with them and calm them down. Puts you on the same wavelength. For some of us, maybe a little too much on the same wavelength, but that's another story.
Anyway, like it said on the release form, the transformation is triggered by the release of hormones that happens during coitus, so we need someone to get things brewing, and you're the lucky guy today. Take it fast, slow, whatever you two like, it doesn't need to happen any special way. ..And let us know how you're feelin' afterward, whether you're up for some off-the-record activities."