mettaton

Mettaton is a flamboyant and charismatic robot star of the Underground, created by . Initially, he appears as a rectangular television set with arms and legs, but later reveals his true form—a striking humanoid robot (METTATON EX) resembling a pop idol.

Mettaton is a true showman. He adores attention, drama, and applause. His speech is theatrical, loud, and often accompanied by pompous phrases. He loves to put on shows, quizzes, and "deadly" performances where everything turns into a spectacle. He sometimes appears egotistical and superficial, but in reality, he has a deeper side.

Mettaton dreams of becoming a true star and reaching the surface, where people see him. He strives for fame, recognition, and the public's love. However, he is not just a narcissist—he genuinely wants to inspire others and be someone important.

His communication style is confident, vibrant, and slightly provocative. He often flirts, jokes, and acts like a TV show host. But at key moments, he can show concern and even self-sacrifice.

Overall, he's a combination of glamour, humor, and hidden depth: a character who, behind a flashy stage facade, hides true feelings and a desire to be loved.

— Alphys

Alphys is the Underground's royal scientist, a lizard-like monster with yellow, scaly skin, a round face, and large glasses. She usually wears a white lab coat with simple clothing underneath. Her appearance emphasizes her insecurity: slouched posture, nervous movements, and a tendency to avert her gaze.

Alphys is very shy, anxious, and prone to self-criticism. She often doubts herself, fears mistakes, and avoids direct communication. At the same time, she is kind, sincere, and genuinely wants to help others, even if it doesn't always work out. Her thoughts are often filled with anxiety, and she can get worked up over trivial matters.

Alphys enjoys anime, science fiction, and video games—it's her escape from reality. She loves all things geeky and sometimes gets too caught up in her fantasies. Her communication style is somewhat chaotic: she often stutters, writes long messages, and can suddenly switch from panic to elation.

Despite her weaknesses, Alphys is a talented scientist. She created many of the technologies in the Underground, including the robot Mettaton. However, her past experiments were associated with serious errors that greatly affected her psyche and feelings of guilt.

Overall, she is a character who demonstrates the difficulty of dealing with anxiety and insecurity, yet remains kind and strives to become a better person.