So it is finished :D The buttons were all sewn on by hand by the way :P yes I am crazy!
The corset itself is made out of two layers of white coutil with a waistband and spring steel boning. It was my fist time making a cupped corset and I am not really satisfied with the result, the shape is a bit wonky and the corset turned out to be to big for me (putting the some pattern pieces in a envelop were another corset size lives is not a good idea), it fits nicely on the body so it is not all to big, but it gives no reduction.
Overall I am happy with it and it gives me a bit of mermaid feeling, I have no idea how many buttons there are, lets stick with A LOT. ^^