@@Nightmare Season,
The mare smiled at the stallion as he proposed sliding down: "Heh, I'm sliding even if I won't have to get down fast! It was my favourite winter activity when I was little, after all. Snowball fights never really speaked to me..." She looked down under her hooves so she wouldn't trip, and continued the ascent.
Nightmare was first to reach the top, and Crystal followed soon after. She led an audible gasp when she took in the view. "For the Love of Cadence, this place is just... If it wasn't in the middle of the Frozen North, I'd build a house here. The view is just so worth it!" The mare seemed really happy for once - the view on her hometown was just beautiful, and there was something really alluring in the snowy wasteland around them. She hopped from one place to another as she took a peek at different parts of the scenery, marvelling at some ice formation or the way sunlight reflected off the glacier, or some other natural phenomena. At some point she pounced and attack hugged the stallion, wrapping her forelegs around his neck and annoucing: "This place is just great! Really, really thanks for bringing me here! Makes me wish I was a painter so I could try and capture this beauty...
She didn't have to take a look at herself to know that she crystallised from happiness - every crystal pony knows how it feels inside. The mare hugged the stallion one more time and let him go, then said in a joyful tone: "I'm so glad to have a friend like you in this mess." Crystal glanced at the slope, then at Nightmare, and made a sly grin. "So... wanna slide down?"