Mac users interested in Sai for mac os x generally download:
Paint tool is an industrious and small tool similar to photoshop but awsome for manga and anime images as well as other photo editing.
This is PaintTool SAI running on Mac OS X via a self contained Wine wrapper. Get this free tool from sourceforge page
Additional suggestions for Sai for mac os x by our robot:
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Showing results for "sai" as the words for mac os x are considered too common