Wait in your room till she sleeps
From Create Your Own Story
When your sister wasn't looking, you slip in 2 of your mother's sleeping pills. Rachel would be out for the night. You wait patiently in your room as your sister takes her shower. A few years ago, you had drilled a small hole in your closet which allowed a perfect view of anyone in the shower. Your cock grows hard as Rachel soaps up her tits and scrubs her pussy. Her ass cheeks were parted just wide enough for you to see her deep slit and ass.
You edge yourself, stopping just before orgasm and repeating to build up as much semen as possible to make tonight more enjoyable.
After about 10 minutes, she steps out of the bathroom and heads straight to her room, almost wobbling on the way there. You quietly follow suit and see that she has passed out on her bed without even removing her towel. Your heat is thumping in your throat as you approach her. You feel slight guilt, but the excitement and growing anticipation of pleasure over powers it.
"Rachel?". She doesn't respond. It seems that pills worked flawlessly.
You: