I was thinking more on this topic, Mrs. and I remembered my H's reply when I asked him why he thought I was sexy. (I was trying to find out what he liked, not fishing for a compliment) He said, quite simply, You like sex.
At the time I thought he just had not given it enough thought to really flesh out that sentence but now I think that that's really all there is to it! For all of us!
The chicks need to know that their men want them and will go after them, if necessary. The fellas need to know that their wives want them.
That's it. That all there is to "sexiness". Everything else is just layers or differences or preferences or variations.
When MrHP says I'm sexy cause I like sex, it just doesn't matter to him that he also has called me "Kramer" (from Seinfeld) a zillion times because of my grace and charm--to him, I am sexy because I like sex and I can turn into a pretty interesting lady in between the sheets.
So I think I could convey to him what my idea of aggression is by talking about what HIS idea of sexiness is. It's really very simple--sexy is going after something that you want. This could be an elaborate setup with lingerie and rose petals or it could be a grab at the kitchen sink or it could be a peck that lingers. It's the intent and not so much the action.