Moody, brooding, and saturnine in temperament, he hates being subservient to Zimreon, but feels honor-bound to serve him. He is often the subject of mockery for his youth (he is only an era old, having been born shortly before the First Exekian War), insecurities and inferiority complex. Despite this, Nechtan is a mischievous, unpredictable sadist and considered highly dangerous even to members of his own kind. He has a special hatred for humans and believes their species should be completely wiped out.
Nechtan is willowy and elfin in appearance. He is described as looking like a youth in his late teens, with prominent ears and dark eyes with only a hint of gray in them. His gaze is predatory and he constantly has a cruel smirk on his face.