Straight upstairs!

You decided that it would be best if you just went straight upstairs to your room. You could find something to wear up there, maybe you might have to deal with baggy clothes or something. You unlocked the door and peaked out and took a few steps out. You were trying to hear if anyone else was on this floor, you didn't hear anything except that football game that was blasting downstairs. Sighing in relief you moved to the stairs and darted up them taking two at a time.

You looked down the hall and saw the bathroom door was open and then you looked at your sister's door. You stared at it as you heard a familiar sound of sex, you could hear your sister moaning through the door. You could hear their bodies slapping together, you just had to take a peak. If you had a chance to see Eric's cock you had to take it.

You moved up to the door which was cracked open and looked in. You could just see the back of Eric, his very muscular back. He was tan all over, and you could see his very powerful thrusts. You saw your sister laying on the bed her hands up pushing against the wall as her tits bounced in rhythm with Eric's thrusts. You stood there staring as you felt your pussy tingle and you felt your breath quicken as you slowly got hornier and hornier.

You had to go!