Hannah forgot to lock it, but the newcomer doesn't

Neither of them heard the door open; the sounds outside got noticeably louder, but they were too preoccupied by the person in front of them to realize that they were no longer alone in the pool house. The door closed once again, and audibly locked. Which, again, the two of them were far too preoccupied to realize.

Jenna flushed with an odd sensation of victory as she managed to get Hannah's bra off, tossing it onto a growing pile of both their clothes on the floor next to the couch. She boldly took control of their kissing, managing to roll both of them on the couch so that Hannah was underneath her and Jenna straddled her, both of them topless and breathing heavily from their exertions and the passion of finally indulging in something they both wanted but had never been able to admit to themselves - or each other - before now.

"Damn girl, I didn't know you had moves like that! Just flipped her like nothing!"

Jenna immediately shot up from the couch as she realized she and Hannah weren't the only ones in the room. Both girls tried to cover themselves up as best they can as their conscious minds struggled to shake off the lust of the moment, focusing as best they could on the new person.