Non linear draft angle

Hi

I want to pull a piece that has a draft angle, but instead of having a linear draft, I want the draft to gradually increase in angle so it turns into a curved draft (i.e. so starts at a shallow angle but increases angle as it is pulled further). Is this possible?

The other way to do this sounds like if I pull the part without any draft, and then carve out the side faces with the curved tool; difficult to explain what I mean, but think of it as if you have a piece of wood and you profile all the sides of the wood using an electric router with a curved router bit. Make sense?

And is this possible?

Thanks..