[BL] Transmigrated as the Villain CEO's Mermaid Secretary

Neville’s fingers trembled as he swiped his access card against the sensor. He practically stumbled through the door as he came inside. The blackout curtains whispered across the floor-to-ceiling windows as he yanked them closed, blocking out the twin moons that hung in Xylos’s purple-tinged sky.

He could see the two moons beginning to align. When they finally overlapped—when the Full Moon came—his body would no longer be his own.

His legs gave out, and Neville caught himself on the edge of the sofa. The cool fabric felt good against his flushed skin, but he knew it wouldn’t last. Already, heat was building beneath his skin like a reactor core about to go critical.

With shaking hands, Neville peeled off his suit jacket and tore the several layers of pheromone patches against his secondary gland. His fingers fumbled with the adhesive before he managed to take it off completely.

Sweat beaded on his forehead, trickling down his temples.

The first sign came.

It started in his legs with a fine vibration. Neville bit down on his lower lip hard enough to taste copper as his muscles spasmed involuntarily. According to Shelly, he couldn’t use transformation pills at times like this.

Weren’t those pills supposed to be used exactly at times like this?

But he also knew that this was nature taking its due.

[Warning! Full Moon in 8 hours!]

"Shelly," he called out, his voice already rougher than normal. "Shelly, where are you?"

There was a pause—too long, which meant that something was happening. When Shelly finally appeared, her form looked dimmer than usual, almost translucent.

[Host, please stop calling me. You will burn through your points like crazy!]

The anxiety in her voice was so clear that Neville almost felt guilty. But then another wave of heat rolled through him.

"Then stop... stop answering," he managed through gritted teeth, his hands fisting in the blankets. "Save your points."

[And leave you looking like this? Host, that’s impossible.]

Shelly’s form brightened slightly as she threw herself into action, her shell-body spinning in agitated circles. She arranged a couple of things that he would need and have access to immediately if needed. All Neville had to do was pull it out of the inventory.

[I’m done, host.]

The system notification flashed across his vision in bold red letters.

[The system will enter complete hibernation mode in 30 minutes!]

[Good luck, Host! Try not to die! (◕‿◕✿)]

The cheerful emoticon felt wildly inappropriate given the circumstances, but that was just like Shelly.

"No!" The command tore from Neville’s throat before he could think.

The countdown froze.

[Halting System Hibernation.]

But Neville, already turning toward the window where moonlight was beginning to seep through the gaps in the curtains, didn’t notice the notification.

His attention had narrowed to three things: the growing ache in his bones, the way his skin felt too tight, and the absolutely maddening itch that was spreading from his legs upward.

He yanked at his tie with enough force to pop a button, the fabric tearing free from his collar. His shirt followed, buttons scattering across the hardwood floor in a sound like falling rain. The air conditioning kicked on, but the cool air might as well have been steam for all the relief it provided.

"Bathroom?" he gasped, already stumbling in that direction.

[No, Host. Your tail is too strong during the full moon—you’ll break the bathtub. We need to avoid unnecessary attention.]

Neville wanted to scream at the oversight, but his jaw was clenching too hard to form words.

Shelly brightened as she accessed his inventory. Suddenly, a portable tub appeared, expanded to its full size in the middle of the living room. It was enormous—easily twice the size of his standard bathtub.

The ocean water bottles she had retrieved earlier were already uncorked, their contents streaming into the tub in a miniature waterfall that filled the room with the scent of brine and deep places.

Neville didn’t remember moving, but suddenly he was at the tub’s edge, his remaining clothes half-torn from his frame. He slipped over the edge and into the embrace of liquid that felt like home.

The temperature was perfect—cool enough to soothe his fever-hot skin but warm enough not to shock his system. He sank until the water lapped at his shoulders. For a brief moment, there was relief. 𝒻𝑟𝘦𝘦𝘸ℯ𝒷𝑛𝘰𝓋ℯ𝘭.𝘤𝘰𝘮

"How much?" he managed to ask.

[You might not want to know about that, host.]

Shelly’s smile was equal parts sympathetic and sheepish. Her form flickered again, dimming perceptibly.

[Just remember to work extra hard after this.]

That was code for "you just spent enough points to make the system weep," but Neville found he couldn’t care. The ocean water was worth it. Every star coin, every point was worth it for this moment of relief before the storm hit.

Then the tub began to shimmer.

Faint blue light rippled across the water’s surface, dancing in patterns. The light intensified, growing brighter with each passing second until the entire tub glowed like a beacon. Neville stared at it through heavy-lidded eyes, his mind too fogged to process what he was seeing properly.

The light was reacting to the Full Moon.

Pain hit him.

Neville doubled over, arms wrapping around his middle as his stomach cramped viciously. His back arched, muscles spasming uncontrollably. He could feel his legs beginning to change.

"Shelly," he panted, "this isn’t... this isn’t like the normal transformations."

The scales were appearing too fast, spreading up from his ankles like silver-black ivy. Each new scale felt like a needle being driven into his skin. He watched, horrified and fascinated all at the same time, as the familiar pattern of his mermaid form began to reveal itself.

[Of course it isn’t, this is a full transformation, host.]

Shelly’s explanation was kind, patient even, but Neville barely heard it over the roaring in his ears. His heart hammered against his ribs hard. Sweat poured down his face, mixing with the ocean water.

But something was wrong—more than it should be.

His arms.

During normal transformations, his arms stayed human. But now, as he lifted trembling hands from the water, he could see the faint shimmer of scales beginning to form there too.

They were delicate things, almost translucent, catching the blue light from the tub and refracting it in rainbow patterns across the walls. Beautiful, in an otherworldly way that made his stomach drop.

[Just... hold on...]

Shelly’s voice was fading, her form flickering like a dying light bulb. Through his pain-hazed vision, Neville could see her growing more translucent with each passing second.

He wanted to tell her it was okay, but every nerve ending in his body fired at once.

Neville’s scream echoed off the walls of his small dorm room, raw and primal and utterly inhuman. His body convulsed, thrashing in the tub hard enough to send water sloshing over the sides in miniature tidal waves. The sensation was beyond any pain he had experienced.

His skin felt too tight, stretched over bones that were grinding and reshaping themselves. The feeling was similar to growing pains but amplified a thousand-fold.

His hazel-brown hair began to ripple. Silver bled through from the roots, spreading through each strand until his entire head blazed with the same luminescent color.

His legs spasmed violently. The bones beneath his skin began to fuse. Scales erupted across every inch of available skin, overlapping in intricate patterns that would have been gorgeous if he weren’t currently dying.

Or at least, it felt like he was dying.

"I didn’t sign up for this!" The words tore from his throat in a voice that was rapidly becoming inhuman. "The system’s mission said save the villain, not turn into sushi!"

Shelly suddenly flickered one last time, her form wavering like heat shimmer.

[Host, I’m sorry, I can’t maintain—]

She vanished mid-sentence, leaving only a faint pink afterglow that faded within seconds. The sudden absence of her presence felt like losing a limb.

The water sloshed violently as another spasm wracked his frame. Without thinking, Neville bit down on his own arm to muffle the screams that kept trying to escape.

His teeth—no, his fangs—sank into flesh, and he tasted copper. Blood bloomed in the water like ink, dark against the blue glow.

"This is the worst!" he gasped when he finally released his arm. "The absolute worst! I want a refund! I want to speak to this world’s manager!"

His complaints devolved into incoherent cursing as another wave of transformation crashed over him. This time, he felt his tail fully form, but something was different.

Through tear-blurred vision, Neville looked down at himself.

The tail that emerged from the churning water was massive. The silver-black scales gleamed with an opalescent sheen that seemed to capture and hold light. But it was the fins that made him freeze despite the ongoing agony.

Delicate, veil-like fins had unfurled along the length of his tail like silk scarves caught in an underwater current. They were translucent threads.

They were beautiful.

They were terrifying.

They were definitely not part of his normal transformation.