It resembles a small dog covered entirely in long hair. Its name is a pun - when written with different kanji (希有怪訝), keukegen means "an unusual thing which is rarely seen".

According to one report, the keukegen is a disease spirit which lives in damp, dark places and causes people in the house to get sick.

• Mizuki, Shigeru (2003). Mujara 2: Chūbu-hen. Japan: Soft Garage. p. 66. ISBN 978-4-86133-005-6.
• Mizuki Road: Keukegen
• CSK: Hyakki Yagyō: Keukegen
• Japanese Wikipedia: Keukegen