What do you do when the beautiful young woman says yes?

I took a chance and asked out a woman who is so beautiful I could choke. She is like a little Evangeline Lilly but younger and actually prettier. I'm effing 40 years old! I sure am past my prime, where I was what girls fell over. I thought she would respectfully decline. Instead, she acted like "what took me so long". What is it that makes such a pretty woman interested in an older man? She is only 27. Is there an example where such an age difference actually went somewhere, minus where $ or power is involved? (I have neither). I am feeling kind of like I am setting myself up for a fall.