Many times I like to get her really close to having an over the top orgasm and then let her down gently to have at it again (peaks). I don't know how many times she can do this and for how long, but at some point I find that it becomes more difficult to get her to a peak unless there is the promise of an over the top climax. After a while, the more times she gets to the brink, the harder it is to get her there again, but when she finally does arrive, the release is usually much bigger after she's had several peaks. By exhausting her energy, I'm suggesting that I might peak her enough times that she can no longer muster the energy to try to go over the top. By doing this I hope to give her as much pleasure as possible for as long as possible, but without her having that big release. Maybe this will give her an appetite for more.