My Girlfriend Sabrina Carpenter wore this to her first college party that my bully threw but i wasn't invited. A few hours in she texts me that she'll be staying the night at his room with his friends.
Its not that you hated your BFF or wanted them to suffer - but your best friend's sister was so cute and well so was his GF - could you really pass up the chance with both of them? Maybe your best friend will never even know you used their sister and GF