2T4U/Jack/Morning/Missy/Just go ahead and let yourself cum
You will probably wake her up if you go any farther than this, and the thought of filling her with your stuff without her ever waking up is just the sexiest idea ever. With that thought in mind, you begin gently humping just with the very tip of your penis, being careful not to break her hymen. With how turned on you are already, this only takes a few strokes before you are ready to blow.
You know what a hymen looks like, most have a tiny hole in them. Wanting to take advantage of this, you press yourself up against her hymen while being careful not to actually break it as you begin to spew your stuff inside her. Despite your efforts to get it through the tiny hole in her hymen though, a lot of your stuff comes right back out with a disgusting farting noise. Despite this and the slight bit of discomfort it causes you due to this not going to plan, you find yourself ejaculating a huge torrent of cum inside your sleeping kindergarten-aged sister. It just feels incredible, the best sex you’ve ever had.
When you are finally finished, you slowly remove your penis and see that despite your efforts you have made a bit of a mess of your 6-year-old sister’s pussy. There is a very definite wet spot on her bed and a bit of your semen dripping down into her butt crack. But, amazingly enough, she’s actually still asleep.