The story of how I walked in on my brother and his girlfriend fucking

Last night was my brothers 19th birthday party. He threw the party out at a wigwam we built in this natural bowl in a clearing in the woods out there. anyways, i know hes out there today just with his girlfriend. and i'm not going to go out there. until my aunt and uncle who live waayy downstate show up and want to talk with my parents, cause they were in the area on a work trip. so my parents aren't there and so they say well lets see this wigwam. I'm not thinking the clearest for many reasons and so i take them both out to the wigwam because i can't act wierd and not take them. so anyways half way there i;m shitting my pants, because also at the wigwam is about 40 empty beers, a beer bong, a bong, tons of shit and worst of all my brother fucking his girlfriend in their tent. So anyways i'm a bit ahead so i yell dude randy and beth are heeere. and i hear this holy FUCK from his girlfriend, and look over at the tent and i was right about what they were doing except not right about it being inside the tent. long story short i saw my brother having sex with his girlfriend