King Enma Jr., usually addressed as Koenma (コエンマ?, meaning "Enma, Jr.") is the son of spirit realm ruler King Enma, and the one who takes responsibility of his father's work when he's away. Koenma usually appears as a toddler with a pacifier in his mouth, though he is said to be at least 700 years old. He can also transform into a young adult form, retaining his pacifier and the letters "Jr" on his forehead. Koenma acts as Yusuke's boss, assigning his cases. His pacifier is a receptacle, which Koenma constantly imbues with his spirit energy. It can create a powerful barrier which Koenma states is to fend off a dark evil sometime in the future. In the anime television series, Koenma is voiced by Mayumi Tanaka in Japanese and Sean Teague in English.