You grit your teeth and go to the kitchen.

You creep past your twin's door, ignoring your thoughts about what could be happening inside that has her leaving the lamp on.

When you get off the landing of the stairs and turn to the kitchen you notice a shifting light there in the darkness. There is a broad shouldered silhouette in front of the open fridge and you breathe easy realising it's just your father.

You walk into the kitchen and he looks over his shoulder at the noise.

"Oh hey, Jon. Can't sleep?" he says smiling. Then he sighs, rolling his head back and closing his eyes. You hesitate in answering and as you approach the fridge your eyes widen. For a second you think maybe you did fall asleep and this is a dream, your cock swelling back to full mast at the scene before you.

Your older sister Betty is on her knees in front of your father in the fridge, deep throating his dick with slow methodical sucks. They're both also fully dressed, at least in terms of being ready for bed, only your father has his pyjama pants around his ankles. Your sister's eyes flutter open and she waves hello to you, unable to speak for obvious reasons. Holding his daughter's head with one hand your father appears to be guiding the pace of her blow job and after three more strokes he slides her completely off of his shaft. The thick wet meat glistens in the dim light, saliva spilling over your sister's chin as she takes some deeper breaths.

"Do you want some milk?" she asks you casually, rubbing the side of her face against the swollen genitals she has been servicing. There's a clink of glass and you see your father take a bottle of milk out of the fridge. He reaches to the table behind him and picks up a glass to pour himself some.

It's hard to focus through your confusion as your eyes flick between your father casually drinking milk and your sister holding his cock, now kissing the shaft up and down in what you can only describe as pure enjoyment.

"This is fucked up," you say finally, causing your father to raise and eyebrow at you as he wipes milk from his upper lip. You don't sound all that put off by it really, the words more like you trying convince yourself that you shouldn't be liking what you see happening here. Your sister giggles before taking the cock back into her mouth.

"It's just sex, son," he says, putting down his empty glass. "We're all consenting adults. You are too now. It's up to you if you want to join in on the ... family activities." He offers you the bottle of milk. There's only about half a glass left in it. The soft sounds of your sister sucking cock in the kitchen feels like it echoes in the empty darkness. She looks at you and somehow she manages to smile with her lips wrapped around your dad's thick cock.

You step forward to take the bottle and your father gives you a nod. You're now standing as close to your cock sucking sister as your dad is and she reaches for your shorts. She grabs the waistband but doesn't pull it down, watching you instead and waiting. Her eyes don't leave you as she takes your father as deep as she can go. You put your free hand on her head, curling her hair in your fingers, and start to pull her off his cock. Taking that as your okay she pulls your shorts down and exposes your throbbing hardness for all to see. Precum has already been dribbling down your shaft and your sister's eyes widen. As soon as your father's cock pops out of her mouth she's on you, eagerly sliding her tongue up the length of you to collect the fluids. Finally being able to taste her little brother seems to drive her wild and she moans, taking the head of your cock past her lips.

You groan and grip the milk bottle tightly. You feel your sister suck you down, her warm mouth so wet she must be drooling nonstop. As she starts to bob on your cock she takes your father's in a hand strokes him at the same time. This is all too arousing and you know you're not going to last much longer, your body already surrendering to the sensations. You take a swig of milk straight from the bottle and feel it cool you a bit but the gagging sounds of your sister as she takes you down to her throat is too hot for that to really help.

"Oh god," you groan, the realisation of how slutty your sister is starting to overcome you.

"Yeah she's good at that," your dad says grinning. He seems content to watch his daughter suck off his son while she 'just' strokes him. His conversational tone is so weird in the context of all of this it turns you on too. Your hips start to move, you can't help it. Your thrusts are met with moans, Betty apparently liking it rough. She's such a slut.

"I'm gonna cum," you say, feeling you should warn her, but announcing it to your family was also a turn on.

"Let her have it, son," you father says, his voice straining. He likes this too. Your sister groans around your swelling cock and sucks you harder. That was enough and you grunt with the first spurt you shoot into her throat. Feeling this Betty pulls your cock back so that you start to empty onto her tongue. She wants to taste your cum before she swallows it. She strokes and sucks you, each pump extracting your semen with such practised efficiency you can barely breathe, feeling your balls empty.

When she finally stops, squeezing one last drop from the tip of your cock then sipping it, you hear your father grunting. He's holding his throbbing manhood at the base, grimacing, then your sister realises what he's holding back and immediately latches on. "Uhhgh...baby," he growls, unloading into his daughter's mouth, hands gripping her head firmly. She swallows audibly and you watch the movements of her throat in stunned silence. Your father's orgasm seems to go on for a lot longer than yours and his pumps are drawn out. When Betty finally pulls away her freckled face is bright red.

"Wow," is all you can manage, feeling twice as drained now.

"Haha!" Your father laughs his deep laugh and grabs your shoulder with his burly hand. "Happy birthday," he says again, pride in his voice. You're too tired to say anything now and just smile weakly. Betty finally gets to her feet and takes the bottle from your hand. She drinks what little milk remains before wiping her chin with the back of her hand then closes the fridge door.

In the new dimness of the kitchen you hear your sister rinse out the bottle in the sink. Seeing your father's shadow bend down to pull up his pants prompts you to do the same.

"Good night," Betty says, giving you both a gentle hug before she heads back to bed.

"You better get some sleep," your father says, giving you one last slap on the back before turning to leave the kitchen. "I'm sure you have a lot of work to do tomorrow. Hmm... I wonder if your sister wants a birthday present too?" You realise he's talking about your twin Jenny and you get a flash of your little sister alternating her mouth between two hard cocks. Hearing your father's gruff laughter again you realise he's joking but admit that there's a slight disappointment in the back of your mind he wasn't being serious. Or maybe he was half serious.

Still, you head back to your room now, noticing Jenny's door is still open but the light is off on the way back. You don't have any other thoughts though and fall into bed and into sleep immediately.

***

You wake up the next morning feeling very well rested. The first rays of groggy sunlight lance through the curtains and you stretch and yawn as you get up. Memories flood back to you from the night before and you freeze.

"Jesus fuck," you gasp, the reality of what happened last night making you sit back down. Your older sister and father have been ... doing things... for probably as long as she's been old enough to work in the Big Barn. They must have had sex too. Does mom know her husband is fucking their daughter? She must. God could Betty suck cock though. The stream of thoughts is almost too much to deal with this early in the morning and you shake your head. Looking down you see that you of course have morning wood. Taking stock of how you feel you find it odd how energetic you actually are. You feel replenished now that sleep has left your system. Then your stomach growls. It was time for breakfast.