This story takes place in Malta where I was on holiday last week with my sister, her husband and our grandparents. The days were spent lounging round the pool either swimming or catching a tan, or wandering around the resort. In the afternoon we went back to the room as it was just too hot.
I was in a 2 bedroom apartment with my sister and her husband. It was okay, although there was a bar just up the road that seemed to stay open forever and kept me awake at night. Not that I was complaining as I got to hear the sister getting a good seeing to each night which made me horny and wet. It took great self control on my part not to scream the place down as I was playing with myself.
On the 5th day, after lunch my sister and grandparents decided to go to Valetta and do some shopping. This meant they would be gone for the whole afternoon. My brother in law, I'll call him Dan, stayed behind as he had a book he was reading and he wanted to get it finished.
About fifteen minutes later I want up to the apartment and decided to have a shower to cool down. Walking through from my room to the bathroom, I saw Dan lying on his back on the bed reading his book. While he was overweight, he wasn't a complete fatty and had a pleasant enough face. Seeing him lying there, I could see my sister being fucked by him and it made me shudder slightly.
As usual the shower got me aroused as I soaped myself all over and then rinsed myself clean. I wrapped a towel around me and walked out the bathroom. I noticed that Dan was now face down on the bed and didn't look round at me. For some reason, I started wondering if he had a hard on and was hiding it from me as he was embarrassed. I decided to find out and went and sat next to him on the bed.