Mary Gowland (メリー＝ゴーランド) is the owner of the Amusement Park. Though he likes to keep his full-name secret, it has become well-known due to Blood Dupre. Because of this he, gets extremely angry whenever he hears Blood's name. Although he likes music, he has no musical ability. The compositions he thinks of are high quality, he just cannot play an instrument to bring the to life. 

He is mostly seen as a gentle man, but only when he isn't in contact with the hatter. Whenever someone, Mostly Blood, mentions his name and makes fun of it, he is thrown into a violent rage (as seen in the ending of volume 1). During the other moments while seeing his friends and working at his park, he is a kind person who cares about his friends.

Mary should have a mid-low to low range voice.