I originally considered basically having what would essentially be a three-dimensional silhouette with no discernable features as Susan's potential not-date in panel two, but I didn't find the results satisfying.
As such, we wound up with a woman whose hair hides most of her face.
I decided a woman made the most the sense, as Susan has considered the possibility that she might be equally attracted to men and women (while not actually having interest in doing "things" with them), and under the circumstances, she would trust a random woman to stick to key parts of that plan more than a random man.
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