Nice clop chapter, but there are a few things you may want to edit. The first thing may seem nitpicky, but the mother's name is Cookie Crumbles, not Crumble.

They were sleem for the most part, then they just magically wake up and start going at it.

That should either be "They would sleep for the most part" or "They were asleep for the most part".

Sweetie grabbed Rarity’s arm giding her to her most pleasurable areas.

There should be a comma after "arm" and the correct word after would be "guiding".

She rose up and lowered her sled carefully on his cock.

I think that should either be "herself" or "lowered, she sled carefully on his cock."

The bed shook and quaked as Sweetie rider her dad like a pro.

That should be "rode".

Rarity wasn’t hard to open op to, but her dad.

That should be "u", but this statement seems a bit confusing and contradictory to what happens in the story.
And lastly, there are several times where you should probably put a comma on the word before a character's name.

“Don’t worry Sweetie. I’ll be right there with you.”

“Come on over Rarity. Show her the ropes.”

“Would you care to give it a try Sweetie?”

“That was just the tip Sweetie…”

“Take your time Sweetie.”