Liz keeps teasing you

You get into your room and take a deep breath. Your cock is still throbbing still...barely perceptibly wet with your sister's juice from when she reached under the towel. You look down and you realize that your towel doing about as much to hide your cock as Liz's camisole was doing to hide her snatch. You were sticking straight out of it, standing harder than you have in a while, and as much as you want it to be for Clarissa, it's all for Liz.

You closed your eyes and focused. Clarissa was just a friend, but she was a friend you'd spilled countless loads of cum while fantasizing about her. Thinking of her taking it in her mouth, on her mocha skin, on her dark brown nipples and the dark brown outer pussy lips and of course draining like a faucet from her pink pussy and ass. It didn't matter that you just blew a load all over the shower. You here hard. Throbbing. wanting to cum again. Now.

And then her skin lightened. The nipples turned from chocolate brown to Liz pink. The furry landing strip of black hair above her pussy turned into the shaved, pale skin of your sister.