That's a delightful series, Zungur. As I've commented in Another Place - #4 especially shows how tuned-in you are to what it is makes girls like me dream of being slaves!
On the matter of 'tunics', I'd quote the Concise Oxford, sense 2 (sense 1 is the military shirt, a different kind of tunic) - 'a loose, sleeveless garment reaching to about the knees', i.e. like the nice brown one I'm wearing in my avatar, though well above my knees. Your #4 is essentially a tunic - and (as you say in the version you posted on DA) 'you have a belt, with which you can reduce length and increase sexiness, once daddy is out of sight'!
@Zungur I'll take the liberty of posting your 'expanded' version of #4:
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