female Frisk, Undertale character, short brown hair, blue and purple striped sweater, blue jeans, heart locket, determined pose, action stance, underground ruins background, pixel art style, ambient lighting, side view, dynamic composition, adventure scene, determination expression, soft texture, retro gaming aesthetic, magical atmosphere, warm color palette, friendly monster companions, 8-bit music notes floating, determination soul, child heroine, indie game vibe, close-up on determined eyes.