Leah replied to me:

...

Mere modesty. They knew their skeletons were likely to be found by another door-opener in 35 generations and wanted to look their best.

Just what I would be thinking of, after a wild session of hot Delta

passion.

Kerril's mother belonged to the "wear your best underwear in case you're knocked down and killed in a traffic accident" school. Kerril suddenly remembered this when she changed into the pale green number (and matching clean underwear).

Jarriet