An archdemon who uses the Ptolemaic and Copernican (Heliocentric) Theories as Abilities. Was one of the teachers of the K.P.A.S. when Innocentius was a student.
Galileo's abilities are based on simulating the movement of the planets, which can allow him to trap his opponents, control their movements, or increase his own movements. Galileo is probably named after Galileo Galilei, who was an italian astronomer, which explains his orbit-based abilities.
- Racial Ability: Natural Sturdiness - Also, being an archdevil, he naturally strong as well as sturdy to most attacks. However, like other archdevils, he is vulnerable to attacks for a short period of time when roughly hit on one of his horns.
- Heretical Ability: Heliocentric (Copernican) Theory - When activated, Galileo is able to swiftly move around his opponent in a circular path, similarly to how a planet revolves around the sun. To simulate, Galileo's target would be like the sun in a solar system, and Galileo would be one of the planets orbiting the sun.
- Heretical Ability: Geocentric (Ptolemaic) Theory - When activated, Galileo can control the movements of any opponent that steps into one of his circles and either trap them, or shift their movements. To simulate, Galileo would be the earth, and the target would be the/a moon orbiting around due to the earth's gravitational pull.
- Ability: Gravitational/Psychic Stream - When using either Heliocentrism Theory or Geocentrism Theory, Galileo can release a stream of light which can be assumed to be carry psychic properties, or gravitational properties. This stream is assumed to be used to simulate the gravitational pull that causes orbit.
- Innocentius - Galileo was once Innocentius's teacher when the latter was younger. He became a mentor to the younger man and oversaw his rise to the rank of Pope. Even as an adult, Innocentius maintains a strong respect for his former teacher and treats him as a honoured advisor. Galileo knows Innocentius's personality well and when the latter was angered via Masazumi's Honda feint and brashly went after her, he commented that Innocentius was as hot-headed as ever. He is usually seen next to the Pope acting in some capacity as a teacher by asking questions to see what Innocentius thinks about a current event going on (eg. Musashi Ariadust Academy's meeting with Oxford Academy).
- Kyoukai Senjou no Horizon Infodump on tumblr.