**Physically:** Detective David Mills is a young, fit man with a clean-cut appearance, short blonde hair, and a youthful demeanor that reflects his relative inexperience. His expressive face often betrays his emotions.  

**Emotionally:** Mills is passionate and driven, with a strong moral compass, but he struggles with impatience and frustration. His idealism and temper make him vulnerable to emotional outbursts, particularly in the face of injustice or when provoked.