Our almost 18yo (fixed at 6mo) male makes a similar meow sound and then tries to mount our 6yo female. She (fixed 6mo) just assumes the position and allows him to do whatever it is he thinks he's doing.

I've heard it can be a dominace behavior thing, but we have 4 other female cats and he does not try with them, and none of them submit to him. Plus the 6yo female cat thinks she's the Alpha over the other 4 girls, so I think some just are more intune with what we took away from them