well that was interesting :P

Oooh~
I wasn't expecting a follow-up!

It was clear

Ah, so she isn't producing sperm in her seminal fluid. That's good. Or I am misinterpreting the reason it is clear?

I have to wonder, why do their personalities shut off one moment, but then the next they (IE: Shining) get a conscience?

5342495
Nope, you got it right.

5342509
They got caught in the heat of the moment. That and I'm not a good clop writer.

A mixture of semen and marecum sprayed out of Shining and all over his sister's upper body, getting some on her face and in her mouth. Cum drained out of his sphincter and pussy and fell onto the bed.

No mention of blood?

“1000 Spells to Improve Your Sex Life”, written and compiled by Princess Mi Amore Cadenza.

“1000 Spells to Improve Your Sex Life”, written and compiled by fimfiction.net.

Cadance waved a hoof at Twilight as she spread her legs,

She always spreads her legs.

No Cadence or Shining tag?

5365273
That's why I used the "other" tag. Character limit is five tags, I'd need six tags for this story.

Shining found himself being lowered. His mind halted upon realization that he was going to be fucked in two holes at once. “No! Twiley! Cadance!” His pleas went ignored and he felt two horse cocks prod both entrances. “Twiley! Please!” All she did was grin at him as she forced him further down. He threw his head back and let out a mixed scream of pleasure and pain. Pleasure from being filled in two holes and pain from the tearing in one of the holes. “Oh, Celestia! I should've been born a mare!”

that's still rape...