It's All Creepy-Crawly Episode 7

After enjoying the newly-installed bath, a strange bug that Lucchini found earlier in the morning is embarrassing the Witches by literally getting into their pants, as well as causing electrical outages around the base. They soon realize that the bug is the core of a Neuroi ship that is sapping electricity from the base, disabling the alarm system, as it feeds a larger unit lurking near the base. After the Witches ensue a lengthy chase for the bug around the base, it is Minna who inadvertently destroys the Neuroi bug when it crawled inside her pants, destroying the larger unit as well. It is technically Minna's 200th Neuroi kill, and she was awarded a medal by the Luftwaffe for the milestone. (from wikipedia)