(EDIT: Dan corrected me on this point in the Keenspot EGS forum. While he didn't elaborate, I gather that the 'remain female for several days' part means before the sex act; long enough for the individual to ovulate, perhaps?)
Sarah's overall reaction to the situation she and Elliot are in is priceless, and Grace's well-meaning candor only makes things worse. Only Grace could be more sex-positive than Diana while still remaining essentially innocent.
I'll try to come up with something a bit more substantial in the near future (preferably not about a comic, too - while I love webcomics, I don't want the community to be just about them). In the mean time, feel free to post yourselves.