My Roommate's Weird Fantasy

So here’s the thing, my roommate and I have been in a steady relationship since we moved into our dorm last year. It’s pretty chill, no drama at all. But lately, things got weird with her kinky side coming out of nowhere. Last night, she asked if I’d ever heard of ‘dominance play’ and then pulled me into her room to show me a video. It was like something straight from one of those adult films, definitely not what I expected from my sweet, bookish girlfriend. She seemed really turned on by it, though. To be honest, I’m kind of freaked out but also intrigued. I don’t know if I can get into that stuff, but she’s insistent and seems pretty passionate about it now. We’re both consenting adults and all, so maybe it’s just me being old-fashioned? Or is this normal for long-term relationships to evolve like this? Has anyone else been in a similar situation or have advice on how to handle it without it becoming a problem?