Your mom looks down at the ass-mask, "Well, I bought this for a reason but it's your choice sweetie; would you like mommy to lock you in this ask-mask?"
You hesitate, you look straight at the camera like a deer in the headlights, then to your mother who just smiles at you. You nod, almost as if in a trance; you neither smile, nor frown, you are expressionless and yet accepting of your mother's suggestive demand.
"Say it!" You sister spouts out loudly.
You mom looks to her with a flash of anger at her lack of tact; but then she looks to you with a smile, "Go ahead, it's okay; just say it dear."
"I'd...I...want you to...put me in your...face mask."
"Ass-mask, sweetie."
"Ass-mask; I want to be in the ass-mask, tied to your ass; mom."
"Aww, that's mommy's good boy," she says, practically speaking to you like a child.
You sister cracks up to herself while trying to hold the camera straight as your mom picks up the ass-mask pieces; first putting on the fitted panties. She shakes her big butt around for you and for the camera as she smiles; she raises her eyebrows excitedly while looking at you.
Then, mom picks up the mask and, though you cower back, slips it on over your head. You jerk your head back and forth, your vision now obscured by the open face mask.
You look to your mom, your face blocked; you looked almost as if you had too much snorkeling gear on. She smiled, giggling a bit looking down at you.
"So, I just want to be sure, sweetie; you want to do this, right?"
You, with all your might, want to say no...but you can't; you can only find the words to say, "Yes mom."
"Okay, then come over here; I'll zip you up to me," mom says, looking at the camera and winking.
You walk on your knees to your mom; she bends down to pick up the belt and you can't help but stare at her shapely ass. You're still staring when she comes stands and looks back at you. She smiles, "Don't worry sweetie, it's not going anywhere; especially for you," you mom laughs while fussing your hair playfully.
She turns her butt towards camera, your sister zooms in until the shot is just mom's butt and you; you look lost and confused. Mom waits for you, then says, "Go ahead, stick it in, sweetie."
You can only hesitate a second before you feeling yourself pushing your face deep between your mother's cheeks until you smell a rank, strong, shitty aroma rising deeply, dankly from her anus which pulsates vigorously with excitement. You try to recoil away but it's too late; your mom has already zipped the mask to the seat of her panties and is now buckling the extra belt to keep you in place.
You moan and whimper; while your nostrils flare, as if on auto-pilot, to absorb a pungent sewer smell from your mom's butt. You gag; choking.
"Aw, I know it's bad sweetie but you can handle it; you'll get use to it, I promise. And you know, mom would never hurt you, right?"
Between panicked exhales, you find yourself, unexplainably nodding in agreement; this seemed like it skirted the lined of hurting.
"Good sweetie."
You retch, almost uncontrollably.
"Don't throw up, that's your first challenge; don't you throw up or mommy is going to be very mad."
Mom looks to the camera and gives a beaming smile before looking back to her son and watching his body shake and convulse, attached to her buttocks.
You calm your stomach, somehow relax your breathing; and finally, mom seems pleased.
"There we go, now you're getting it."
Mom grunts softly and you feel her cheeks contract, squishing your head a bit with a tight pressure; then, in the dark space between your mom's cheeks, you watched, in horror, as her anus pulsed out firing out a thick, potent blast of gas right into your face.
BRRRRRRRRRRRRRRRRRRRRRRRRRRPPPPPPPPPPPPPP!
Mom's fart ripped loudly and proudly, it sounded like a duck call coming out. Your body shook and immediately tried, without avail, to break free from the stench. Your sister hopped around excitedly, capturing and enjoying the action; she pinched her nose, smelling a little of mom's monster in her direction.
"Oh, God mom; that's putrid," your sister complains, laughing.
Mom giggled, "I know, it's that damn broccoli and cheese; does it to me every...RRRRRRPPPP....ahhhh, time."
The second fart made you scream as your eyes watered from the gas attack that felt like it burned the skin right off your face. Your nostrils are bombard with a rank, rotten vegetable aroma. Opening your mouth is not much better as the drying fart air quickly overcomes every taste bud on your tongue, giving you the sensation of tasting your mother's shit, every quality of it, from salty to sweet; though, admittedly, there wasn't much sweet in this batch.
"Can you smell that bro? The broccoli and cheese," you sister asks you.
Mom turns to look at you and smiles as you nod, "I hope it's as good coming out as it was going in dear," she says, laughing softly so as to not crush your spirit entirely; she was still your mother, after all.
She scrunches her face, closing her eyes as she pushes. On your end, you watch her anus push in and out before finally firing out...
PRRRRRRRRRRRRRRRROOOOOOOOOOOOOOPPP!
"Ahhhhh, that was a good one sweetie; you should enjoy that."
The part that was pushed you do do this, did; but unfortunately, that didn't control the part that had to smell it. That part of you was tormented beyond all reason by mom's latest gassy blast that blew up like a bubble against your face with such intense, immediate odor.
"Help!" You mustered enough fight to yelp out; stupid and pointless as it was.
"Aww, don't worry sweetie, mommy will help you...here...how about..." she concentrates, pushing a little
RRRRRRRRRRRRPPPPPPPPPPPPPP!
"Ahhh, there, does that help my little baby?" Mom giggles, rubbing the back of your mask covered head. The touch soothes you and, though nauseating, you more smoothly inhale mom's remnant gas from her ass.
"Mmm, that's my good boy."
"What are you gonna do next mom," you sister asks eagerly.