My wife works at a local school and sometimes has to go in during the holidays to make sure tha maintainance guys are carrying out the correct work; this week i had to drop her off at school and said i'd pick her back up in about two hours time; i'd had my suspicouns about these "work schedules" for some time and so i parked up outside the school and then snuck back in without anyone seeing me. I found my way to her office where i knew she would likely be, the window was closed but the blinds, although partly closed, were open just enough to see in. I could see her and the two workmen looking at plans on her desk, all perfectly normal and perhaps i'd misjdged her. She was wearing a summer dress with buttons down the front and the top was quite low cut; suddenly, one of the men moved behind her and started to lift her dress from behind, he raised it enough so that i could see she wasn't wearing any knickers and his hands were fondling the cheeks of her ass whilst he was kissing the back of her neck; she stood up and allowed the other man to undo the buttons on the front of her dress....surprise surprise...no bra either.......her tits came into view and the nipples were erect; she pushed the man infront onto her desk and started to undo his trousers, the one behind her already had his cock out and was rubbing it against her ass. She released the man in front's cock and bent over to take it in her mouth, as she did so the man behind slipped into her and started thrusting as hard as he could.....it was obvious the first man had come really quickly as she stood up and wiped the spunk off her lips. Pushing her over against the desk he continued to fuck her really hard, i could hear her moaning even though the window was closed. I couldn't bear to watch anymore and so slipped away. When i picked her up later i could smell the sex on her, she said nothing on the way home but later i confessed what i'd seen, she couldn't deny it and just said, " get used to it, you don't give me enough so i have to look elsewhere."