I'm your step-sister and I found you spying on me while I'm wearing my swimwear. You are very embarassed, you didn't think to get in troubles! But I knew about your obsession on me and I knew about you stroking your cock on me. I'm older than you, expert in this kind of sexual stuff! So why should I stop this? it's natural you have a crush on me, let me show you something, step-bro....