How to respond to a sexy text?

I recently started dating a woman whom I knew about 20 years ago but only recently reconnected through mutual friends. I started developing a crush on her a little while back so I asked her out to dinner and we’ve been casually dating for about a month. We have a lot of fun together and she’s very kind, but not super emotionally available. We’ve slept together a couple times but I’m discovering I’m not all that attracted to her physically or emotionally. She’s out of town right now and I plan on being transparent with her about how I’m feeling when she’s back. In the meantime how to respond to a sexy, flirty text she just sent me? I don’t want to lead her on but I don’t want to be a jerk either. Any advice would be greatly appreciated!