Otto Houlihan is a lieutenant employed by Christopher Carrion. His nickname is the Criss-Cross Man, and the very mention of him is enough to instill fear among Abaratians.
Otto Houlihan is tall with yellowish skin and a checkerboard board pattern tattooed across his face. He wears long purple robes with blood-red stitching. His crimes, according to Jimothi Tarrie, are numerous. He is known throughout the Abarat as a notorious assassin and hunter.
Houlihan makes his first appearence on the island of Gorgossium at Midnight. He has come from Commexo City with an associate of Rojo Pixler named Dr. Voorzangler to show him a device used to spy all across the Abarat. When Carrion refuses to give it back, Voorzangler protests. Carrion strangles him for a few moments until he stops insisting he take the device back, and Houlihan leads Voorzangler out of the tower.
Later, when Candy finds herself held hostage by Kaspar Wolfswinkel, she speaks to Houlihan on the phone. She thinks his voice is smooth and snake-like as he interrogates her about the Key that John Mischief had given her, and Kaspar had forcefully taken from her mind. He tells her he is coming after her to take her back to Gorgossium.
After Candy and Malingo escape and conjure a glyph, Houlihan arrives with an army of Mires, a monstrous brand of stitchlings. Though the Mires get close to them and nearly knock the glyph out of its flight, Houlihan does not get close. With Candy and Malingo gone, Houlihan goes to the embarassed Kaspar's house and takes the Key, telling him he has no real power now that he no longer has what Carrion wants. Kaspar pleads for Houlihan to help him off the island, bringing up that they used to be friends and went to school together. Houlihan reluctanly says he will do what he can, but no promises.