As always, I'll be blunt and honest and tell you what you need to know, not what you may want to hear.
Your entire approach to your photos of her is wrong. You seem to concentrate on what she's wearing (or not) and the pose and then you just stick lights where they don't get in the way.
If you learned about lighting, and the very basic physics involved, you'd know what can't work in lighting terms and modify the pose etc to suit the lighting, but you don't seem to do this.
Your lighting is hopelessly wrong. Before you do anything else,
1. Move that softbox so that it's pointing directly at her, rather than from behind and in front as it is right now. It also needs to be higher, but your choice of hat may not suit that.
2. Now, switch it off, but leave it where it is, because it's acting as a useful reflect.
3. Put a honeycomb on your key light, to both control the spread of light and to prevent flare.
4. Put it behind her, directly behind, if that doesn't work you may have to move it a bit to camera left, , if her right breast gets in the way of the left one, but start with it behind and, with any luck, completely hidden by her body. If necessary, move it further back too, the perspective effect will help to hide it.
5. Establish the power setting by test shots, it's easier and usually better than metering in this situation.
6. You will now have the effect you want, it may or may not be far too dramatic, but that's the starting point.
7. Switch the softbox light on if the results are too extreme, start at the lowest possible power setting, adjust upwards in small steps until you're happy with the result.
8. Make small incremental adjustments to the softbox position until you're happy.
That's all there is to it, it's fissics innit?
That frilly top may not be right, and maybe the hat isn't either, but these are easily changed.
