You can recall only two members of that dialogue, bulb-lit or otherwise. It was the only one you had with that group of people, you are sure of it—some of these sureties are intuitions as much as memory—as though you are sometimes able to see a counter or tag associated with a given event in your internal catalogue which shows at a glance its number or relevance, regardless of the content recalled. Memory metadata. It is not an outcome of repetition; this was a single occurrence more clearly intuited than those with many. The thin lady and the one with a hat: the combination of impressions associated with them are significant enough to unconsciously mesh with your own sawtoothed internals.
The thin lady was playing a game, presumably ruining the entire experiment. The one with a hat was quietly aware. There were other people there of course, over-asserting—given the context—too loud and attention-grabbing, generating too much noise to hear. Ignore them.
The thin lady: seemed surprisingly wide, when she shifted, like a piece of paper. Flat-lunged, was your thought at the time; overly sat-upon. The one in the hat: sagged at the loins, seemed stern about the shoulders—hard and pinched and conical, but wobbly at the inner thigh. Thin-boned, was your thought at the time, non-uniformly dense; as though flesh bellies were hung too high or too low on the bone. What flesh there was, and it may not have been as much as seemed to be presented, you obsess upon it now, managed to look gross and distended and off-centre.
They both had the appearance of long-term sitters; on different paths and from different starting shapes, but both becoming increasingly buttock-shaped or buttock-dominated over time, organs and flesh settling at the point of greatest resting or abrasion. Perhaps that too differentiated them from the others present, made them seem more dedicated to the task, despite that undercurrent of subversion.