"Dinky, muffin, please come back down." Derpy calls out. The pegasus looks around, making sure there's no onlookers. Thankfully she doesn't notice you. Her hoof dips under her pillow and starts to massage her tender bits again. She whimpers a bit in ecstasy.
"M-muffin, sweetums! Please come down here! I want to talk to you about something, ah, something important!"
What in the world is she doing? You watch on. Dinky descends the staircase to see her mother, still sitting on the couch with a pillow shamefully covering her crotch. Only now that pillow is sharing the space with Derpy's hoof.
"Mom, are you.. Uh, touching your-"
"Muffin!" Derpy says. She seems much more stern out of nowhere, "I need to be very honest with you right now..."
Derpy looks around, losing her strong composure just as quickly as she gained it. The pegasus seems very confused about what she's going to do next. She taps her chin with one hoof and continues clopping with the other as her daughter watches on in disgusted wonder.
"Muffin," She finally says, "I noticed you didn't know what I was doing. And I think as a young girl you gotta know about your coochie."
Derpy lifts her pillow aside to illustrate her point. Dinky, being only a filly, blushes in shock and can only stare in awe at her mother's glistening womanhood. You can hardly bare to watch what happens next. But it's like a trainwreck and you can't find the strength to look away. Derpy doesn't move her hoof away, instead she starts petting her kitten harder and in plain view of her daughter.
"Dinky, I-I... I want you to le-learn what this is! It's called cl-clopping at it feels soooo good!"
"Mom I-"
"Dinky! Look at this!" Derpy sticks her hoof out to her daughter, which is now soaked her in her female juices. "Sniff this, it's got my musky stuff in it! It'll make you horny! "
Dinky looks disgusted, but she obeys her mothers wishes and sniffs the cum-battered hoof. This is perhaps the most surprising thing you've seen all day, but Dinky keeps sniffing it! She's actually aroused by the smell!
"Mom, it's really stinky, but.." The filly blushes, "But I kinda like it. Could I maybe have a taste?"
Derpy nods and her daughter starts to lap at the femjizz coating her mother's hoof. You honestly can't believe your luck. You always had a thing for incest but you never thought your voyeuristic tendencies would pay off like this! In fact, you can't resist reaching between your haunches and giving yourself a little rubdown as you watch the mother and daughter go at it.
"Oh Celestia!" Derpy cries out and wraps her legs around her daughter's head. Before Dinky could react, she was shoved face-first into her mother's dripping snatch. It was only eight years ago that Dinky Hooves was expelled from her mother's womb, and now it feels like she was going back in. The walls of Derpy's snatch were slick with her musky fluid, so much so that Dinky had to swallow it just to keep from drowning! Finally her mother screamed in delight and let loose a deluge of cum onto her daughter's face. The the two ponies, mother and daughter, just laid there with their bodies intertwined. Eventually though, Dinky was let out from between her mother's legs. And wouldn't you know it, the first thing she did was climb into her mother's waiting hooves and cuddle with her on the sofa.
Well, it started out as cuddling, but Derpy forced her lips onto Dinky's and she allowed herself to surrender to passionate kiss of her mother. You think you saw some tongue in there, but it wouldn't surprise you. Gosh, all this has you really hot and bothered. Maybe, if those two were so open about incest, they'd be open about a third party...