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
All you knew is that your mom was going to confront your sister for dating your bully. Now you get a text from your sister telling you "Bro! Mom is lubing him up real nice for me."