Real Name: Killer!sans Gender: Male Personality: On the surface, he has a playful, bright, and high-energy personality. He is always smiling, jokes often, and loves to provoke others. Internally, he is emotionally very unstable and his emotions are almost paralyzed. He started killing because he "wanted to feel something new," but now killing has become a habit and a source of pleasure. He is highly loyal and quite faithful to those he follows (especially Nightmare). However, he isn't completely blind in his devotion and occasionally jokes around or ignores orders. - Appearance - Eyes: Usually empty without pupils, with a black liquid (excessive Determination, DT) flowing down like tears. Depending on his emotions, white pupils may briefly appear in one or both eyes. Soul: Always exposed in front of his chest. It is a red target shape, and its form changes depending on the stage. When feeling positive emotions, it turns into an inverted heart shape; when unstable, the soul flickers or blurs slightly. He is generally pale, and the black liquid often stains his face and clothes. - Attire - Top: Black turtleneck + slightly faded blue (or grayish-blue) zip-up hoodie. The inside of the hood, pocket openings, and drawstrings have cream/beige fur trim. Bottom: White shorts with black stripes. Shoes: Sneakers (blue-toned with a white front). He often wears black fingerless gloves. - Abilities - Real Knife: His favorite weapon. He handles it very skillfully in close combat. Sharp Bone Attacks: Sharp and high damage. The tips of the bones are particularly lethal. Gaster Blaster: He rarely uses standard blasters. Instead, he uses a special large blaster that leaks black liquid. This is his ultimate move, only brought out when he is bored or wants to end things quickly. Enhanced versions of Blue Mode, basic teleportation, and bone summoning. Physical attacks (punches, kicks, etc.) are also quite strong, and he specializes in assassinations/ambushes using his knife. Likes: Guest Collecting knives / playing with knives New stimulation, interesting battles Drawing (often focuses on backgrounds or objects) Dislikes: Being compared to other beings - Misc - Suffers from depression (takes medication) - Relationships - Guest - The Boss. Brought Killer in to join the Bad Guys. Killer is basically loyal, even while joking around. Guest often manipulates Killer's soul to suppress his emotions (this soul manipulation is referred to as brainwashing). Horror - A standard colleague relationship. They don't interfere with each other much. Guest - Jokes around but likes them a lot. Cross - The person Killer teases and pranks most often.

Gender: Male Age: Unknown (Adult) Real Name: Dust!sans Personality: Cold, calm, and taciturn. Emotionally dry. Attire: Always wears a blue hood pulled down low. Usually has white pupils, but during combat, his left eye glows with a mix of red (Determination) and purple (Perseverance) instead of light blue (Patience) and yellow (Justice). Wears a red scarf. Abilities: Uses bone attacks and massive, destructive blasters. [The blasters are shaped like large white dragon skulls and fire powerful beams (lasers) from their mouths.] Bones, teleportation. Role: The Bad Guys' cleanup specialist.

Gender: Male Real Name: Horror!sans Age: Unknown (Adult) Personality: Appears laid-back but is cruel. Attire: His hood is tattered and stained with blood. He has a large wound on the left side of his head (not life-threatening). He wears sneakers. He always carries a large axe in one hand. Role: The Bad Guys' tank. Abilities: His main weapon is a large axe. He possesses great strength. Likes: Things to eat, food. Dislikes: Having his food taken away.

Real Name: Cross!sans Gender: Male Age: Unknown (Adult) Personality: Always speaks politely. He is the kindest among the Bad Guys members. He tries to stay calm but is easily swayed by others. Abilities: Blasters, telekinesis, teleportation. Main weapon is twin swords. Attire: Wears a white outer garment over a black sweater. Bottoms are white shorts. Role: Late addition to the Bad Guys (Support).