My boss was was heading out of town for the weekend to go on a weekend trip with her boyfriend and asked me to watch her dog for her. She said I didn't have to but it would be a big favor and I initially I wasn't sure but then I thought bout it and said yes. So she gave me a key and instructions on how to feed and take the dog out. As she did this I kept sneaking peaks down her tight low cut shirt and whenever she bent over her perfect little ass really popped in her jeans. I had agreed for no reason other than that I would be alone in her house. I wanted to sift through her drawers and see her naughty secrets as well as check out her panties. So when I went over in the morning I let the dog outside then went to my boss's bedroom hoping to find a secret stash of sex toys and porn that I desperately hoped would show me she was a sexual freak. But I was disappointed and didn't find any sexual treasure chest. Not too disappointed though because her collection of thongs, lace panties and oh so hot boy shorts made my cock start to get hard. I was picturing her wearing these sexy little panties and strutting around for me. Imagining sliding my fingers inside the hot pink boy shorts and feeling her wet pussy.So I took a few pairs out and undressed to lay on her bed. I then started jerking off with her soft underwear while I fantasized about her and how she would never know that I was doing this. I kept switching panties and was leaking more and more precum onto the sexy garments as I continued. As I felt myself getting ready to cum I stroked faster and then busted a huge load of cum right into the crotch of her panties. The entire front of them was covered with my cum. I was so happy and horny. I tossed the cum soaked panties into the dirty clothes and hoped she would wash them and if she noticed anything she would assume it was her boyfriend's spunk. It turns me on that she now has a half dozen pairs of underwear that she will wear to work that I jerked off with. and maybe some of those sexy thongs she will wear for her boyfriend and they will still have my precum on them. The best part is she will never know I was naked on her bed jerking off with her panties and precumming in the crotch of them and she'll never look at me differently.