The inward structure of this piece is fashionably organized demonstrating ninja characteristics. The artist used an effective method of outlining the ninja with a white stroke to add contrast between the ninja and the background. Evidentally, ninja's and nighttime go together well, and you can't deny a ninja with black ninja gear on.
The ninja's eyes create the sort of "mysterious" impression on his face, as if he's ready to retort to an attack. The viciousness of the facial expression and his garments only leads us to one conclusion...
...danger in the nighttime.
