Creating a seperate opacity strength controller for an outline

gibrril_fa945a6cee

Hi all,

I'm currently trying to get some things done in a cartoon-style effect, but I ran into a problem dealing with opacity.

I'm trying to have my figure wear a sort of see-through item, ( I toned down the opacity way to much in the attached file, to show what is happening :) ) but whenever I turn the opacity down, the opacity of the outline also gets turned down. For obvious reasons I would like the outline to have a seperate opacity controller so that the outline of the cloth stays as sharp as the outline of the figure itself.
I know I could use the outline of a seperate render and composite the pic together, but I was hoping I wouldn't have to render twice or more to get this fixed.
Can this be done without postwork?

If so, how?

Thanks a lot,

Me