My stepsister has a boyfriend and still prefers me 😈

My stepsister has had a boyfriend for years. He's a good guy; kind, honest, hardworking and seemingly faithful. He's a good guy, one of those who are few of you nowadays. The problem is that my stepsister is addicted to my dick; She prefers to have me inside her, than her boyfriend of years. I feel a little bad for him, but it's his fault for not knowing how to satisfy my stepsister.