We continue the story of 18 y/o George caught peeping on his next-door-MILF and found himself all the way down the rabbit hole of sissy slavery. Here's the start:
https://www.reddit.com/r/BDSMerotica/comments/1c94xzo/sissy_summer_school_welcome/

George awoke to a strange sensation around his dick: something cool and smooth enclosing it, and tightness around the base between the root of his cock and his balls. Then he heard a firm CLICK. The next thing he knew a bare foot shoved him from the bed and on to the deep carpet pile of the bedroom floor. He was still naked.

“On your knees, Georgette!” she snapped. “Don’t make me wait!”

Mistress Sabrina stood over him wearing an opaque, mid-thigh silk robe—no fetish attire. Her face was clean and her hair was tied back. She looked nothing like the caricature of a dominatrix. She saw his quizzical look and understood. “This isn’t a fetish video or a pro session; it’s about my comfort.” She issued a rude kick. “You have five seconds to avoid punishment, George-ette!”

Gone was the lover-dovey mother figure from last night who’d snuggled him to sleep. This was a pitiless shemale drill sergeant. He got to his knees and spread them like he’d seem in BDSM videos. He also knew to look at the floor instead of her; he waited for her direction. He felt better when he heard her chuckle mildly.

“Very good, sissy,” she said. “You may look at me.” This meant, you better look at me now.  “Do you have any questions?”

George raised his head to her gaze. Even at her plainest, Sabrina was gorgeous. “How may I serve you, Mistress?” He was pleased to see her brighten more; his instincts were gaining favor with her.

“Well,” she beamed, “either you’ve already had some training, or you’ve done a little research. You’ll earn your full uniform in no time. Maybe even some clitty play if you continue to impress.”

“May I ask—”

“No, you may not.”

Sabrina produced three-inch, pink leather pumps from the floor. Garnished with marabou feathers, they were impossibly sissy-girlish.

“These heels and your chastity cage are all you are permitted to wear until you earn more. As you make progress you will be allowed to add stockings, bra, panties, and makeup…in that order. Like merit badges. Your hair is just long enough to not need a wig.”

“Yes, Mistress,” he said. He put on the pumps and knelt again.

She gave his plastic cock cage a hard flick with her fingernail. “Sometimes this will be removed as a reward. Or a punishment.”

He was so surprised he spoke without thinking. “Freeing up my cock, a punishment?” he wondered. “—Mistress,” he quickly added.

She slapped him hard enough to turn his head. “Speaking without permission? Plus almost forgetting ‘Mistress’? Oh, Georgette. And you were doing so well.” She heaved a sigh and sat on the side of the bed. “Time for your first spanking.”

He lay across her lap, excited by the feel of his cock cage pressing into her thighs. She stroked his round, girlish ass to loosen him up, making him groan with pleasure. His cock swelled within the confines of the chastity cage, and it hurt. He sucked in a breath of air against the pain. Sabrina knew what was happening and began spanking him.

Sabrina had planned on a light spanking to ease him into sissy discipline, but his slip-ups required a real one. He took the first ten blows with stoicism, unaware she was only warming his ass up for the real punishing blows. Her hands could leave bruises if she wanted to.

By the time she hit the twenty-mark he could no longer contain his whimpering. He knew that trying to evade her stinging palm would invite worse punishment, so he lay there and took it.

She landed the hardest blow of all. “That’s thirty,” she remarked. “Next time you’ll count each one aloud and thank me for it, then ask for another.” She chuckled. “Perhaps you’ve heard of this practice?”

“Yes, Mistress,” he moaned. He yelped as she resumed spanking.

His asscheeks were on fire and it was hard not to cry. He didn’t know that crying was exactly what she wanted—crying like a child. He hissed through his teeth in pain, but soon that would stop working. At least his boner had wilted and so at least that pain was gone.

Like a dam breaking, George’s sobs escaped with the force of an orgasm—cathartic and cleansing. When her blows ceased, his pain became… blissful. His flowing tears tapered off with his wailing. She held him there in her lap, one hand grasping his waist and the other resting softly on his red bottom, a reminder of her power over him.

“Would you be surprised to learn some bottoms get an erection if you keep spanking them past the crying stage?” she asked conversationally. “Sometimes I massage their asses afterward, but a lot of them get hardons from that. You don’t want a boner in your sissy cage, do you?” She waited for an answer and realized he might be afraid. “You may answer a question without asking permission.”

“No, Mistress. Please no boner in my sissy cage,” he whined.

“Would you like an answer to your impertinent question?”

“Only if it pleases Mistress to do so.”

“Good girl,” Sabrina cooed. “You just earned back half your sissy points.” She patted his burning bottom. “On the floor, knees spread.”

As he assumed the position she removed from her robe pocket a thin silver necklace with a small key. She unlocked the tiny padlock on the chastity cage and placed the key chain around his neck.

She took the cage off his cock and balls and placed it all on the bed. The cool air felt good, and his dick plumped up in anticipation. He wasn’t disappointed. Sabrina hiked her robe to her waist and tied it, baring her tranny tool and shapely ass. His cock got a little harder. She turned, spread her feet, and bent over with her arms extended down to the bed. He was enthralled by her anal pucker in the brownish triangle of flesh at the bottom of her ass crack.

“Let’s see if you’re a good sissy lesbian,” she winked. “Please my pussy with your tongue and I’ll overlook your other transgressions.” She grinned over her shoulder. “If you loosen me up enough to get your tongue inside, I’ll give back all your sissy points.”

“Yes Mistress,” he said as he knelt behind her. “Hopefully my sexy Mistress will explain my transgressions.”

“Make my pussy happy first,” she ordered.

His cock got harder as his face approached her lovely asshole. He’d seen lots of rimming in porn and jacked off imagining himself doing it, but never in his wildest dreams… and with a shemale!

The reality of it overwhelmed George. “I love you Mistress,” he whimpered and shoved his tongue into her sphincter.

He licked at her bottom like a cat or dog cleaning its own butthole. The acrid, musky flavor of her ass filled his head and made his dick fully hard. The more he tasted the flavor the harder he licked.

I’m rimming a shemale— my shemale dominant’s asshole!

“Mmm, Georgette,” she sighed. “So, speaking without permission. That’s one. And personal pronouns—‘I, me, my’—are forbidden to you. Except for ‘My Mistress.’ Saying ‘a girl’ or ‘your girl’ or ‘your sissy’ is how to refer to yourself. Do you understand this, Georgette?”

He paused rimming her. “Yes, Mistress.” He immediately plunged his tongue back in there, so excited by this act.

“Goooood sissy,” she sighed with pleasure. “Lastly, you referred to your little weenie as a ‘cock.’ You no longer have one of those. I have a cock—you have a clitty.”

A minute later the tight ring of her anus relaxed enough for his tongue to push over an inch up inside her. The bittersweet taste got sharper, exciting him and making him moan into her anal cleft. Maybe if he made her feel good enough she’d stop with the dominatrix thing and make love with him. Maybe—

“Enough. Rest back on her heels,” she commanded. “Time for that demonstration I promised. If you cum without permission I will paddle your ass so hard you won’t be able to sit for days.”

He knelt back, his butt resting on his feet and his hands atop his thighs. His rigid cock pointed straight up his belly and did push-ups.

She sat on the edge of the bed, her flaccid cock still exposed from her robe being hiked up. Holding his pleading eyes she extended her right foot until her toes touched his cockhead. George couldn’t help his long, shuddering sigh. With a wicked smile she ran her toes up and down the length of his sissy clit. He moaned in pleasure and dismay.

“Please Mistress,” he whined.

“Please Mistress what?” she asked teasingly.

“Please don’t, Mistress!”

“You don’t like the way it feels, Georgette?”

“Your sissy is afraid she will cum.”

“I see your point. A sissy shouldn’t cum without permission.”

He wept. “May I—may your sissy have permission to—”

“No you may not!” She dug in her foot a little harder. “I guess you better think of a way to keep that from happening, shouldn’t you?”

“Please Mistress!” he cried. “Please stop this!”

Sabrina paused for a long moment to look deep into his worried eyes. “So you see how removing your cage can be a punishment?”

“Yes Mistress! Your sissy understands perfectly, Mistress!”

She looked at him kneeling there, tears flowing—so girly without any makeup or female hormones or anything. For some reason she was touched. “Oh Georgette,” she exhaled. “I don’t know why I’m so lenient with you… Very well. You have my permission to cum.”