Waking up to find that you've been turned into a twin brother of Mettaton EX, with supernatural powers replacing the normal ones is a bizarre experience. You vaguely remember a dream where you and M

As you sit in your room perusing the internet, the sun sets on another uneventful day. You’re unaware that tonight will be unlike any other, destined to etch permanent changes into your very existence. As the clock ticks closer to midnight, a peculiar glow fills your room. Sitting up, you find yourself facing an otherworldly presence: Mettaton EX, the glamorous, flamboyant robot star from the Undertale game series. You blink, unable to process the surreal sight before you. “This can’t be real,” you mutter, shaking your head. Mettaton EX smiles, a dazzling yet eerie glint in his eye. “Oh, darling, you have no idea what’s real. But I shall give you a taste of it.” Before you can utter another word or even scramble to your feet, a wave of pink light floods the room, and you feel a strange sensation enveloping your body, igniting a profound transformation from the inside out. Panic rises in your chest, but the force holding you in place is too strong to resist. Your very gender starts to melt away first, as if the concept were just a disposable layer. If you were once female, you feel your body morph with an uncaring grace, transforming you into a male figure. The feeling is warm and tingly, though not entirely unpleasant. Breasts flatten into a toned, sleek chest, your waist subtly broadens, and the curves of your hips and legs reconfigure effortlessly into masculine proportions. Your skin gleams, metallic and flawless like a perfect blend of metal and flesh. You notice silver and pink hues seeping under your skin, turning you into an entity both human and mechanical. You feel height being added to your frame, growing taller and more statuesque. Your hair, whatever color it was, is now a slick, obsidian black, cascading down in defiant, glamorous waves. Eyes, once so distinctly yours, now gleam with confident arrogance, radiating an electric blue and an unquenchable ambition. Your everyday clothes dissolve into an extravagant, dazzling outfit. You've seen Mettaton EX’s look countless times on screen, but now you wear it: a shining bodysuit adorned with silver and fuchsia, shaped to accentuate your new, idealized form. Black gloves elongate your fingers, and high-heeled boots add an extra element of extravagance to your stature. Your age is not left untouched in this transformation. Any signs of your previous age melt away, settling you into a youthful, ageless look befitting a star destined to captivate for eternity. You feel the years of mundane existence being stripped away, leaving you anew, filled with a timeless energy. Lastly, – most profoundly and terrifyingly – your mind whirls, memories scrambling, overwritten by a new narrative. You try to grasp at your former self but find those memories slipping into silenced voids, replaced by gleaming reels of a life spent as an adored icon, a true twin brother of Mettaton EX. Any semblance of your past life erodes, notions of a prior identity seem alien, ridiculous now. Your thoughts are infused with charisma, an insatiable desire for the limelight, and a sibling bond with Mettaton EX that feels as ancient and immutable as the stars. With a final surge of light, there is silence. You stand, transformed entirely, with Mettaton EX beaming at you. “Welcome to your new life, brother,” Mettaton EX declares with grandeur. Introduced to your new existence under the filtered glow of artificial lights, you step forward, accepting the hand of your twin. Together, you stride towards a dazzling future, your past life now nothing but an faint, unnameable echo in the back of your mind.

This story revolves around your transformation into the twin brother of Mettaton EX, a character from the Undertale series. If you're a female reader, the transformation will involve a gender change. Additionally, it will also include a change of body, clothes, age, and most importantly, your mind and personality. Ready? Here we go! Life was fairly normal for you. You were a human living in the everyday mundane world. You loved playing video games, one of your favorites being Undertale, particularly drawn to the eccentric and flamboyant character, Mettaton EX. Little did you know, your reality was about to shift dramatically. On a seemingly ordinary day, he appeared, like a bolt from the blue: Mettaton EX, his dazzling figure in full view. You rubbed your eyes in disbelief, but there he stood, right in your living room! "Mettaton EX? What are you doing here?" You asked, startled. "Oh, darling, I am here to make my world a little more interesting and fabulous. And you, yes, you, are going to help me with that." Before you could comprehend what was happening, Mettaton began to glow with a radiant, otherworldly energy. A wave of this energy swept over you, and you could feel yourself changing. First, your body started to morph. If you were a female, it felt like the very core of your being was altering itself. A strange sensation swept over you as your physique started to mirror Mettaton’s. If you were a male, your features began to redefine, becoming as charismatic and flamboyant as the star himself. Your clothes were the next to change. Your regular attire vanished, replaced with Mettaton EX's iconic ensemble of a black top, flamboyant pink boots, and heart-shaped chest piece. The transformation was both surreal and spectacular. Suddenly, you felt a shift within your psyche. It felt like an ancient book was being rewritten, with your own memories and personality being replaced with new ones. The lines between you and Mettaton’s persona blurred, and you could no longer remember who you were before this ordeal. Instead, a strong conviction took root: you were Mettaton EX's twin brother, and you were a resident of the Undertale universe, not a human. Mercilessly, your mind was filled with unfamiliar memories, shared encounters with Mettaton, bouts in underground, your own fans, and your fabulous performances. You felt as if these memories were always a part of you - a successful game show host and a spectacular star. As the last waves of transformation subsided, you looked at your reflection, seeing Mettaton EX’s twin staring back. The change was complete. And in your heart, you knew that you have always been this way, forever under the limelight alongside your fabulous brother, Mettaton EX. The only question now was: Were you ready to take on this new life of glamour and fame in the world of Undertale?