My family had moved into this house a few months earlier, and I called dibs on an old attic that had been converted into a bedroom. The place was huge, by teenager standards, and it even had its own stairway, so I could come and go as I pleased. There was a small window in the front that looked out over the driveway and a large window in the back by the stairway that overlooked the backyard.

I had been spending my day watching a little bit of television up in my room, and I had just decided to become a little more productive so I headed over to the back stairwell to make my way into the garage when I paused to look out the back window. The back part of the house was L-shaped, and from my vantage point, I could see most of the backyard, including the back porch. Right next to the porch was our back door that led into the kitchen, and running down that wall was the window to the lower bathroom.

As I gazed out my window, I noticed movement in my peripheral vision, and I turned my attention towards it. What I saw caught me completely off guard. The bathroom window was wide open, and directly inside was my older sister taking a shower. Up until that moment, I was completely unaware that my sister had a habit of opening the bathroom window while she was taking a shower to vent off the steam, and because of that, I suddenly found myself staring at her bare breasts as she shampooed her hair.

I could literally hear my heart racing as the reality of what I was seeing hit me, and the excitement of it all flowed through my body. This was soon followed by a feeling of sheer panic as I realized that there were no curtains or blinds on my window, and that I could be easily seen by her, so I ducked out of the way. I found myself in sheer disbelief of what I had just seen. Did I just see my sister naked? I thought to myself. I do not think that she saw me. If I am not careful, I will get caught and get into trouble. I quickly built up my courage. “Okay, one more look.”

I peeked up and looked out, she was gone, but I could still hear the sound of water splashing down upon the surface of the bathtub. “She must be rinsing off the shampoo,” I thought to myself. It was then when she stepped a little more forward, and I could see the side of one of her breasts protrude from the side of the window, and I watched with amazement as a stream of shampoo suds ran over the top of her nipple. I hid myself again.

After a few moments out of sight, I built up my courage again and went for another look. As I looked down at her again, I, in turn, found her staring right at me. She was completely shocked to find her brother looking at her, and her eyes were as big as dinner plates. I went into full defense mode and tried to play it off by looking away and acting like I did not see her. My sister slammed the window shut and then called out for my mother. I was a dead man.

I bolted down the stairs, my mind was racing, trying to come up with a way to explain what happened. Seeing my sister naked was an accident after all, but would my mother believe that? As I reached the living room, I was met with the sight of my sister wrapped in a towel complaining to my mother about how perverted her little brother was. My mother, in turn, did the unexpected. She laughed her ass off!

I apologized to my sister for what happened, told her that it was an accident, and that it would never happen again. I even assured her that I would put something up to cover the window for privacy. My sister turned around and headed back to the bathroom, and I returned to my room to find something to cover the window with.

Searching my room for something that would easily fit over the window, I found an old Batman and Robin beach towel that I had gotten when I was six. It had seen better days and it even had a few holes in it, but it was perfect to provide privacy, privacy for me, that is.

So, over the next year and a half, my sister continued to shower with the bathroom window open to vent out the steam, and I, in turn, kept a silent vigil over her. To make sure that her shower experience was uneventful, of course.