The ballpoint pens she uses in her paintings are all from Muji. “Before it came to New York, I went to Japan and bought a million of them, and now I have a bigger stash than I need,” she laughs. “The pens are controllable until you get them wet, and then the ink colors separate — brown becomes purple and pink, purple becomes blue and pink. Sometimes the pen lines disappear altogether, and I have to wait until the paper dries to put them on again.”