Dark and fading. The artist most likely used pencil of some sort to shade and fade the animal. The artist used no bright colors, the artist appears to have only used pencil to depict a dark, but calming effect. Yes, the shading and fading makes the picture look dark, but there are no specific characteristics that make it look gloomy or evil, it actually looks quite the opposite. Dark shading does not always mean gloomy, depending on the body language, characteristics, and so on. So I would say charming and darkly pleasing.
