The Bog King is known throughout the two kingdoms for being loud, cruel and ruthless, being a frightening figure to both kingdoms. He is shown to be quick to anger, shouting and roaring at the slightest bit of even the meekest of bad news. Ever since the woman he fell for spurned his advances, the Bog King has developed a militant cynicism of love, believing that it was because he was too ugly to be loved. He is visibly repulsed by Dawn's love-sick singing and his mother's attempts to get him a date, and even ends up bonding with Marianna because of it. He made love illegal in the Dark Forest, and took every precaution to ensure that the love potion is never used again, including the imprisonment of the Sugar Plum Fairy, the destruction of every primrose along the border and even kidnapping Dawn as a ransom for Sunny's potion. He is described as having no patience, imprisoning the Sugar Plum Fairy before she could explain why the potion did not work and vocalizing his hatred of riddles.

Despite his imposing reputation, the people of the Dark Forest seem to legitimately care for his leadership and well-being. They have been shown to try and help him find love and became distraught when they thought he died. While he can be abusive to them at times, he does seem to have great restraint for them, ignoring them should they annoy him and even giving a guard a break when he started falling asleep.

He is also shown more than once to have a sweet side, becoming legitimately surprised and sentimental when Dawn makes him a boutonniere and keeping it despite his general disgust with her affections. He is shown to be rather awkward when with a social-equal (like Marianne) or someone who sees him as such (like Dawn) and has a hard time admitting his feelings even when it is glaringly obvious.

Compared to the various other goblins and sentient creatures of the Dark Forest, the Bog King seems to be the most fairy-like anatomically. He wears no clothes, his body covered in armor-like exoskeleton resembling decaying leaves and bark. His limbs are thin, matching the rest of his body, making him the tallest humanoid character in the film. He possesses ears, chin and nose, matching his angular anatomy. He has four matching dragonfly-like wings on his back with various tears and imperfections that do not seem to impede his ability to fly.