So i wander out and around the corner to discover, indeed, one of my girls going at it on said couch, obviously some serious action going down, legs tangled, shirts edging their way up, whole business.
"HEY!" I shout "People can SEE you, so perhaps you should NOT!"
My girl immediately jerks to a sitting position, to reveal... another girl underneath her.
After giving them a final stern look, i then flee back to the classroom, lest they see me cackling my pervy fannish heart out, because i blatantly just interrupted some schoolgirl femmslash.
later, i found out that the other girl is actually my suitemate's student, and that she wandered into class 15 minutes late with the excuse that she'd lost track of time *snerk*