Topping

The injection burned cold, then warm, spreading through your groin in a slow, heavy wave. Your cock twitched hard under the robe as the serum settled. Kylie received hers with only a soft sigh, her thick soft cock giving a visible pulse between her thighs.

Dr. Glasscock disposed of the syringes and gestured toward a side door. “Informational component. This way.”

You were led into a small, dimly lit TV room with two reclining chairs facing a large screen. The door sealed behind you. Soft pink and lavender light filled the space as the video began.

The footage was slow, looping, and relentlessly focused. Close-ups of two cocks side by side—one thicker, one smaller. Feminine and masculine hands measuring, weighing, comparing. A calm, almost clinical female voice narrated over the images:

When in a sexual relationship with a trans woman, it is important to remember that you should compare cocks often…

The smaller penis is the bottom…

Size determines role…

The smaller cock submits…

Compare. Accept. Submit.

Intercut with the comparisons were lingering shots of the smaller cock being stroked, kissed, locked, or ignored while the larger one received attention. Every few seconds the screen flashed a clean graphic:

SMALLER = BOTTOM

Your cock strained under the robe. The serum made every pulse feel sharper, more sensitive. Kylie watched the screen with parted lips, her own cock visibly swelling. The messages repeated, layered, sinking deeper until the video finally faded to black.

Dr. Glasscock’s voice came over a speaker. “Session complete for tonight. Return to your villa. Rest. The serum will continue working.”

The walk back felt hazy. Kylie stayed close, her arm brushing yours, the heavy swing of her cock under the short robe impossible to ignore. Inside the villa the ocean stretched dark beyond the glass. You both dropped the robes. Kylie stretched, completely unselfconscious, her cock hanging between her freckled thighs.

“I’m still sticky from earlier,” you muttered, voice rough.

“Go ahead and shower,” she said. “I’ll wait.”

You stepped into the clear glass enclosure and turned the water on. The heat felt good against your skin, but your cock stayed stubbornly hard, the serum and the video’s words looping in your head. Compare. The smaller penis is the bottom.

When you finished and stepped out, Kylie was sitting on the edge of the California King, still naked, legs loosely spread. She looked up at you with a soft, expectant smile.

“Come here,” she said. “Let’s finally compare.”

Your heart hammered. You walked over until you stood between her knees. She reached out, wrapped warm fingers around your cock, and stroked it once, slow and deliberate, bringing it to full hardness. Then she lifted her own cock with her other hand and pressed the two of them together, side by side.

The difference was immediate and undeniable.

Yours was longer. Thicker. Even with the visual weight her thinner post-transition body gave her, the side-by-side truth was clear. The head of her cock didn’t reach as far as the ridge of yours. Your fingers could circle both shafts, but hers looked almost delicate next to the heavier girth of your own.

Kylie stared down at the comparison. Her freckled cheeks flushed. A slow, surprised breath left her.

“Oh,” she said softly. “You’re… bigger.”

The words sent a dark, satisfied heat rolling through you. Your cock twitched hard against hers, smearing a bead of precum across her shaft. The hypnosis video’s mantra still echoed, but now it cut the other way.

You wrapped your hand around both cocks, keeping them pressed together so she couldn’t look away from the size difference, and gave a slow, deliberate stroke.

“The video was pretty clear,” you said, voice low. “Smaller penis is the bottom.” You squeezed gently, emphasizing how much less of her there was in your fist. “That means you owe me your ass tonight, Kylie.”

Her eyes flicked up to yours. The same mischievous spark from childhood was still there, only now it was mixed with something hotter and more uncertain. She bit her lower lip, then nodded once.

“Yeah,” she whispered. “Okay. You’re bigger. I’ll… I’ll be the bottom.”

You released her cock and cupped the back of her neck, tilting her face up. “On your knees first. I want that mouth on the bigger cock before I take what’s mine.”

She slid off the bed and dropped to her knees on the rug without further protest. Her freckled hands rested on your thighs as she leaned in and took the head of your cock between her soft lips. The wet heat of her mouth made your hips jerk. She sucked slowly, carefully, eyes glancing up every few seconds as if still processing the new order of things. Spit soon slicked your shaft. The sounds she made were soft and wet and beautifully submissive.

You let her work for several long minutes, one hand resting in her damp ginger hair, until your cock was throbbing and shiny. Then you pulled her off with a gentle tug.

“Bed,” you ordered. “Hands and knees. Ass up.”

Kylie climbed onto the California King, the same bed you’d stared at when you first arrived, and settled into position. She lowered her chest, arched her back, and reached back with both hands to spread herself open for you. Her smaller cock hung hard and dripping beneath her, the head already shiny against the sheets. The sight of her—childhood best friend, freckled, soft-bodied, presenting—sent another thick pulse of heat through your bigger cock.

You knelt behind her, rubbed the head of your cock up and down the cleft of her ass, then pressed against her tight hole. She was smaller, tighter, and the resistance made both of you groan when the head finally popped inside. You gave her only a moment to adjust before feeding her another inch, then another, until your hips rested flush against her soft cheeks and your balls pressed against the underside of her smaller cock.

“Fuck,” she whispered, voice high and shaky. “You’re… really bigger. It feels so much thicker.”

“Because it is,” you said, gripping her hips. “And smaller means bottom. That’s the rule.”

You started to move.

Long, steady strokes that dragged almost all the way out before sliding deep again. Each thrust punched soft, helpless sounds out of her. Her smaller cock swung and leaked beneath her, untouched, leaving wet streaks on the white linen. The wet slap of your hips against her freckled ass filled the room along with her broken moans and your low, satisfied breaths.

“Listen to you,” you murmured, leaning over her back so your chest pressed to her spine and your lips brushed her ear. “Taking a bigger cock like a good bottom. Say it while I fuck you.”

“S-smaller cock means bottom,” she gasped between thrusts. “I’m the bottom. I’m your bottom tonight.”

“Good girl.”

You fucked her harder after that. One hand reached under her and wrapped around her smaller cock, stroking it in time with your hips—not to make her come yet, just to remind her how easily your fingers swallowed her whole. The dual sensation of stretching her open while handling her smaller cock pushed both of you closer to the edge.

“Don’t come until I say,” you ordered, squeezing the base of her cock firmly. “Bottoms come last.”

She whimpered, hips stuttering, but obeyed. You kept using her—deep, claiming strokes that made her knees slide wider on the mattress—until your own breathing turned ragged and the tight heat of her body became too much. With a low, broken groan you buried yourself to the hilt and came, flooding her with thick, pulsing heat. You felt her clench around you as the first spurt hit, her smaller cock throbbing hard in your fist.

“Now,” you growled.

She came with a high, broken cry, spilling over your fingers and onto the sheets while you stayed buried deep inside her. The aftershocks ran through both of you for long seconds.

You carefully lowered the two of you onto your sides without pulling out, curling around her back, one hand still loosely holding her smaller, spent cock. Her freckled body trembled against yours. Outside, the ocean murmured against the shore.

“Mine for tonight,” you whispered against the back of her neck. “Bigger cock means I get the bottom. Sleep with me still inside you.”

Kylie nodded weakly, already half-asleep, her smaller cock still cupped in your hand, her body stretched open around the cock that had measured longer and thicker. The serum kept your nerves singing. The hypnosis kept the words looping, only now they settled in the other direction.

Smaller penis is the bottom.

And tonight, the smaller one was hers.