Just Figured Out I Like DDLG?

So yeah, after some pretty wild fantasies involving me getting into this Daddy/Daughter dynamic with my partner, she's in her twenties, I finally had the courage to mention it to her. She looked at me like she knew all along and laughed. 'Oh really?' she said, as if we were already neck-deep in roleplay when I'd been just daydreaming. It was a surprise for sure, but kinda cool too. We ended up spending hours talking about it, and I have to admit, it felt weirdly therapeutic. Like, here's this thing I thought only existed in my head, and now we're having actual conversations about it. Now, here’s where I’m getting a bit lost. Is it normal for couples to suddenly dive into these kinds of explorations? Should I be concerned if we're both enjoying the roleplay aspect so much it's starting to feel real? Any advice out there on how to navigate this new dynamic while keeping things playful and fun without letting them spill over into some weird gray area?