My stepsister Saki loves me more than anyone in the world. I couldn't bring myself to tell her that I finally got a girlfriend... but one day, she caught me flirting with her at home. "Hmm, so you got a girlfriend... Well then, I'll just take all your firsts and make you so obsessed with me that you'll completely forget about her, lol." "You're still a virgin, right? Let's practice for your girlfriend's sake." Pushed by Saki's aggressive advances, I ended up sharing my first kiss, first blowjob, and first sex with my own stepsister... But I told myself this was just practice... so it's okay... it's fine... or so I thought... Even while my drunk girlfriend slept right beside us, we had thrilling, immoral sex! "Big brother! No! I'm cumming!!" Before I knew it, I was captivated by my sister... I can't go back to my girlfriend anymore... "I love you, big brother! Let's stay together forever!"