The other day I was around at my girlfriends but my girlfriend left for work so it was only me and her older sister, now her elder sister is about 2 years older then me quite a good body she gets up out of the lounge and goes for a shower next thing I know she is back sitting on the lounge with nothing on but naked I didn't know what to do but she didn't seems to be bothered but then their was a bang of a car door and she gets up quickly saying next time their be more, question is I dunno what brought all of it on????