Huge

Samus thought for a moment and then smiled.

"I want the biggest, girthiest dildo you can get. Also some lube would be great."

"Affirmative, retrieving items"

Suddenly, a 14 inch long 10 inch wide horse dildo and a giant bottle of lube materialized in front of Samus, who licked her lips hungrily.

"Perfect. Thank you AI"

"It is pleasing to know you are satisfied, Samus Aran."

Samus turns back to the dildo in question, and with no hesitation sticks it on the ground, kneels down, and sniffs from the balls to the tip. This is a real stud cock, an alpha to slam her boy pussy until she cums everywhere with reckless abandon.

She starts licking the dildo, not caring about the taste of rubber, fantasizing about a real cock of this size in her boy pussy. (Maybe a real horse if that's what readers want) she licks around the tip, and then sinks down on it, pleasurably discovering she has no gag reflex, feeling her throat distend to take the horse cock.

It can't get the whole way, even with her wet throat, but has a remedy for that. She takes the giant bottle of lube and rubs it all over the giant dildo. She sinks down on it again, idly noting that the lube tastes really good, before slamming it down her throat. It glides much easier this time, and she finds herself staring at the balls of the dildo. She comes back up with a satisfying squelch from her throat as the dildo leaves it, and notices shes painfully hard.

She smiles, it looks like she has to relentlessy pound her prostate to get rid of that ungirly hardon. She smatters more lube onto the cock and stands up over it. She squats down, feeling the flared head push against her asshole. She needs this in her, shes burning for her ass to be stretched to the limit and broken in pleasure, walls scraped smooth. She secures herself in place, and slowly starts applying weight to the dildo. She lifted her legs up and let gravity help her.

It wasn't totally unexpected when all of it slid past her ring and bottomed out in her fat ass, but that did nothing to numb the absolute bliss she felt from her intestines being plugged. She wailed like a banshee as her cock released cum in a thin but highly propelled stream from the pleasure her ass was just put through.

She sat there cumming for several seconds, before lifting herself up and slamming down again. And again. And again. She had never felt anything CLOSE to this pleasure before, and just kept spurting out sissy load after sissy load, losing herself to the pleasure. She pulled off the dildo and moaned from the cool air rushing into her asshole, before she promptly fell back down and plugged it up again. She wanted, no she NEEDED to never take this out again.

"A-AI! Get me something to hold this inside me please!"

"Affirmative."

A harness with a thin belt where her ass would go materialized in front of her. She quickly put it on and fastened the belt tight, keeping the dildo lodged balls deep in her boy pussy. Every step she took sent waves of pleasure throughout her body, and she couldn't stop cumming everywhere. Now the question is, what next?