Too much...

It's too much... the gloriously evil pleasure of watching your little angel take you down to the root, her gags and slurps sounding sharply in your ear.
"Mmm...." she's humming and rubbing your balls as she frees her tits from their confines. You can feel it bubbling. You can't stop it...
"Riley...you're going to make me..." Too late...
Riley moans with delight as you burst, emptying your balls into your baby girl's throat.
"Mmm! Mmm!!" she pumps the load into her mouth, and pops free to let some of it hit her face. The sight is awful and sexy, and terrible and erotic. You're going to hell. Do not pass GO. Do not collect forgiveness. Divorce, then prison, then hell.
"Thag you, dahhee." Your cum spills over her chin as she laughs. She swallows what's in her mouth, then grabs a nearby towel to clean up the rest, and then to clean up you too.
You collapse onto to steps of the hot tub gazebo, dazed.
"Can't.... can't...." you're broken.
"Daddy..." she kneels in front of you, but you turn away, curling into the fetal position.
"No..." The images won't go away. "I'm a monster."
"Dad. James..." she's stroking your hair. "Stop that. You're not a monster. You're my father who loves me. And I love you. You needed some relief, and I wanted to help you..." She sits next to you, putting her arms around you. "It's ok! I'm not going to tell anyone. Please, daddy. Don't be mad."
You can't help it. You love her. You're a black-hearted monster, but that much is true. You put your arm around her. "Why.... why did you do this...."
"Because I love you, daddy. You don't have to be afraid. I'm not scarred by this. I'm happy I finally got to do it! I've been wanting it for so long. I don't care what people think. Besides... your cock is amazing! Tasty... I didn't mind the sweat! And your cum was tasty too! Matt tasted...well I don't give a fuck about him, so never mind about that."
"We can't do anything like that ever again, Riley."
"But....." she puts on a pout. "I didn't get to..."
"And you aren't ever going to get to, Riley. What we just did was bad enough..."
"That's not fair..." she's whining now.
"Fair?!?" you are so incredulous. How does she seem to have the moral high ground here?
"I'll make you a deal, daddy." She sits in front of you. "If you..." she swallows. "If you fuck me, really fuck me, I won't ever ask again. It'll be our little secret, forever."
"Riley... I can't..."
"Pleeeeeease...." she always knew how to weasel into getting what she wanted from you, but this... "Please, daddy. Just one time... one wild time, and I'll never ask again, I promise."
"Even.... even if I wanted to... even if I agreed to... how would it happen? Allison's in your room, and your mother... the house is full of people, Riley."
"We'll find an opportunity, I just know it."
You can't believe the words that are coming out of your mouth, but you say, "One time? And that's it?"
"I promise!" she smiles.
"...........ok." You feel something die inside when you say it. Your conscience, maybe? Your soul?
Riley throws her arms around you, and kisses you passionately.
"Thank you, Daddy! You won't regret this! I'll be such a good little fuck, I promise." You are almost sick from how wrong this is, but what's worse is how aroused you are by it.
"Just... keep a lid on it until then...."
"Of course. Mum's the word."

After a few minutes of quiet togetherness, you escort her back up to the house. What have you agreed to? This is so wrong... but it felt so good. One good fuck, to get it out of her system. You can do that, right?

You and the girls play card games, board games and talk about school and other things for a while. Riley spends most of the time with one of her feet planted in your crotch under the table, with Allison blissfully ignorant. Eventually, the girls start to doze and you bundle them off to Riley's room.

Soon after, the headlights of an Uber swing into the driveway.