Buffy knows a thing or two about torture. From both ends of the thumbscrew. But this, this is something.
"Look," she points out, "it's not like we weren't into each other before, right?"
"Right." Buffy tries to focus only on how carefully Martha is looking into her microscope, tries not to notice how her neck bends, her eyelashes, the flush on her cheeks. "But not like this." Only the roughness of her voice, only that Martha sounds every bit as tortured by trying to hold back as Buffy feels, keeps Buffy from just freaking killing herself right then and there.