Why choose?

"So I can just ask them their intentions one at a time, and if they just want a ride or to be a friend with benefits or a sexfriend, whatever, it'll be ok even if it becomes a de facto harem?"

"If everyone's honest about it, I don't see the problem."

"Then be honest with me. You want to do it again and again after that. Be my sibling with benefits, so to speak."

"Come on Dick, think with your actual head, not the little one. We can't be honest with anyone else about that, so there is a problem."

"You have a problem. I have a solution. Accept and give into your feelings. You have to keep a secret anyway, why not feel good about it at night, or in the mornings?"

"Damn it, quit charming your way into my panties. It has a good chance of working."

"Then let me in. Let my not-so-little head stretch you out and make you climax once again. Let my hands explore your body once more and let it be claimed by me."

You place your hands on her right tit and between her legs while kissing her neck. She doesn't resist as you make out with her while getting your hands beneath her underwear. She searches with her hand for your stiff member and finding it, strokes it through your pants. You both end up pulling each other's clothes till you're bottomless.

"Let's get into the 69 position. I've never eaten anyone out before."

"That's oddly sweet. I'll try not to slack off on my end. If you make me moan, you're going to feel it. I expect the same."

So it was that you started a sex act you hadn't practiced on Eileen first while experiencing a blowjob with the woman's head in a different position than usual. For all that talk of ending it before, not only is she wet now, it's been kept clean otherwise. You use all the tongue techniques you read about, even that alphabet thing, and her moaning feels good on your cock.

"You're so good at making me feel good. I want your cock inside me. Make me addicted to your cock."

She moves into the reverse cowgirl position and inserts it in herself. She twerks on your cock and it's great. You grope her ass cheeks.

"Yeah, neither of us can do without this. I just hope you don't get jealous when I'm giving it to your friends too."

"I'd have set it up silly, but if I do, you can use your cock to punish me for my hypocrisy."

"I don't see how it would be a punishment when you already love my cock."

"You'll find a way, and what I love is you. There, I admit it. I'm so perverted to fall for my little brother but I don't care. You win. I'm yours."

"Alright, I'm going to cum to mark my territory. Take it inside."

"Wait a second, do it somewhere else. Today is..."

You cum deep inside her, keeping it in as she finishes her explanation.

"It's not safe. It wasn't before either but I wasn't keeping track because I wasn't sexually active yet. I got swept up in the moment and didn't remember till you reminded me. Whatever we do, we can't afford to breed, so are you going to pull out anytime soon?"

You pull out and without tissues nearby, she sucks you clean and walks to the bathroom with her clothes in one arm and her other hand keeping your sperm from spilling anywhere. She hurries up when you both hear mom pulling up to the driveway. You start dressing quickly.