The Time I fucked [M]y cousins G[F]

This story was inspired by a memory from a question that i saw yesterday on r/askredddit . The question:

Redditors, who slept with the partner of your best friend, what happened?

Not my best friend but my cousins GF. I still feel bad about it. We were close and i really shouldnt have. So it’s the day of a big sports match our team against our biggest rival. The three of us, [M]y cousin(31) his g[F](35) and [M]yself(26), were just hanging out together the whole day drinking beer and just passing the time until the game starts. About 2 hours before the said match is supposed to kick-off I tell them that I am feeling rather drunk and want to go back to my apartment to go and have a quick shower and a fresh change of clothes seeing that it was a hot and humid day. I leave them at her place and tell them ill meet them there before we make our way to go and watch the match. Im back at her place fresh out the shower 30 minutes before kick-off and she lets me in only to discover my cousin out for the count on her bed.