(A few brief notes: this is a comfy, softdom story. Nothing too explicit happens other than bondage and light hypnosis. There's also a brief mention of chastity, and a few brief mentions of diapers/ABDL items. Nothing too deep, but I know some people might prefer to avoid that.
I wrote the subject, Ash, with they/them pronouns, and don't reference any specific genetalia. Their partnet, Kate, is written as a woman, but doesn't have to be. Feel free to replace them with whatever you like the best :)
I Hope you enjoy!)

Ash sighed as they finally got back to their apartment. It had been a long, grueling week of work, but it was over, and they had a long weekend to look forward to.

They called out "I'm home!" while taking off their shoes, and noticed a note above the shoe rack.

"Ash - I have a surprise to help you relax! Go straight to the bathroom - you'll find another note in there :) - Kate"

Ash smiled. Kate and them had been dating for almost a year, and Ash was still amazed at how caring - and kinky - Kate was. They proceeded to the bathroom, where they found a blindfold with another note on it.

"Take some time to shower and freshen up! When you're ready, knock on the door, put on the blindfold, and kneel here." Ash put down the note and smiled as they stripped. Soon enough they were in the shower, hot water running down their body.

Ash took their time scrubbing their body clean, and felt a growing sense of calm obedience as they did. The conditioning Kate had put them through came to mind - "as you wash your body, feel your worries wash away as well".

Soon enough, Ash felt sufficiently tranced and ready. They dried off, knocked loudly on the door, and slid the blindfold on. As darkness engulfed them, they kneeled obediently, waiting for Kate to guide them to whatever surprise she had in store.

Ash didn't have to wait long for the door to swing open. They heard a sharp breath in. "Ash, I'll never get tired of seeing you like this. Let's get started, okay?". Ash nodded and let themselves get guided up, and into what they figured was the bedroom. They were guided onto their soft bed and laid down.

"I know this week was tough. That's why tonight we're going to get you all nice and cozy, and then get that mind nice and blank. Just leave everything to me~"

All Ash could do was let out a contented moan a mix of anticipation, conditioning, and tiredness bringing them into subspace already.

"First, let's get you locked up again. I know, I know, we agreed to no long-term use for awhile - but I don't want anything down there interfering tonight, okay?"

Ash nodded, and let out a weak "Okay". They had to admit, they loved chastity, just not being locked for huge swathes of time. At least, not yet.

"Good! Let's get it on .... and there! Does that feel okay?"

Ash felt their genitals get swallowed by the chastity device, becoming locked away as they had so many times before. They fidgeted a bit to make sure it was on okay, before replying with a quiet "Yeah".

"Good~ Now we can get on to the main event. Lift your butt." Ash complied, and felt a bulky piece of cloth being pulled under them. Ash knew it was a diaper, and smiled. "Good, you can go back down".

Ash felt a coolness as Kate sprinkled talcum powder all over their crotch before pulling the thick diaper up and securing it. "There, now doesn't that feel good? No need to worry about getting up, or using the bathroom. Just nice and calm and safe, right?"

"Mhmm~" Ash just let out a contented sigh, happy to let Kate work her magic.

"Okay, lift again for me! There you go, let's get this nice and secure". Ash felt a cover being secured over their diaper. The waistband was pulled tight and locked, followed shortly by similar bands around their thighs.

"There, now that's not coming off. Now, remember your booties? Let's get them on too, you're doing so well". Ash felt booties being pulled onto their feet - soft cotton booties, with dull metal spikes on the bottom. Walking, or even standing, isn't possible with them on. Not that Ash could stand or walk anyway - their mind was drifting away, their body obediently on autopilot.

Kate secured the booties' ankle straps snugly, and locked them on. "There we go. Now you definately aren't going anywhere~". Kate ran her hands up Ash's legs, eventually reaching the diaper. She patted it several times, eliciting a small moan from Ash.

"Okay Ash, sit up for me and put your arms out. Let's get you in your jacket, okay?". Ash immediately obeyed, their body moving sluggishly onto position. Ash heard the straps and buckles of the straighjacket jingle around as Kate guided their arms deep into the sleeves.

Kate was an expert at putting Ash in this straightjacket, and was quick in getting all the straps tightly secured. Before long, Ash was stuck in a tight hug, unable to move their arms - only able to wiggle back and forth a bit. The bottom straps of the straightjacket caused dug into the thick padding of the diaper, only adding to the soft tightness of the whole outfit.

Kate spent a few moments smiling as she inspected her handiwork, and then snapped. "Ash, wake up for a moment".

Ash's mind snapped back into their body as they heard the trigger. They struggled for a moment against the bondage, before Kate stopped them with a hug. "Shh, shh, I'm here. You're doing so well. Do you need anything before I bring you back down?"

"No, just some water and warm milk when I'm under."
"Of course!"
"Thanks. For everything. I love you."
"I love you too, dear. Now sleep for me."

Ash's mind went blank as they heard the trigger. Kate pushed their body softly down, laying them down in the soft, big bed.

Ash began the final steps of the bondage - securing Ash into straps running along the bed, stapping them snugly to the bed. She spoke softly, deepening the hypnosis, blanking Ash's mind more and more as she finished her handiwork.

Kate slipped a pair of headphones playing white noise and subliminals onto Ash's head, and stuck a pacifier into Ash's mouth. Ash began suckling it softly, deep in trance, mind as bound as their body.

"Sweet dreams. I'll check on you soon." Kate smiled as covered Ash's bound form with a blanket, turned off the lights, and closed the bedroom door.