…making a bad pun, apparently. See, for this butterfly:

I used the tempera/India ink resist method to create the black outlines.

If you don’t know how an ink resist is done, here is the method I use:

1. Draw the basic outlines, mainly of the parts that need to be black in the final product.
2. Fill in the parts that need to stay white with a white tempera/gouache paint. Let that dry at least overnight.
3. Cover the entire paper with India ink and let it dry.
4. Rinse the paper under water and gently scrub the underlying paint off.
5. Let the paper dry, then use watercolors to fill in the other colors.

It takes a few days, but I like how it turned out. Probably should have used a tougher paper to stand up to the washing, but it works well enough.