Ghost

Ghost (ゴースト) is the UMA that embodies ghosts.

Appearance
Ghost wears a stitched white cloak which has nails pining it down onto it's fairly buff body.

Personality
Ghost enjoys feasting on people's souls. It is also incredibly sadistic and will do whatever it takes to instill despair into it's victims, even break it's own rules.

Unbelievable Arc
The addition of UMA Ghost was offered as a reward for the successful capture of UMA Autumn.

Ragnarok Arc
Ghost is added by Apocalypse as a reward for accomplishing the Four Season UMA quests, which saves Fuuko from dying and continue living as a ghost. However, it kidnaps her with intent on eating her later before being summoned to Ruin by way of massacring an entire city to tell Ghost so they can "become friends". Ghost is then asked by Ruin to leave nothing of Fuuko's soul behind before leaving with Ruin. As a result of Ghost's addition also brings with it the creation of "Astral Projection", allowing a user to separate their soul from their body, as demonstrated with Lucy, and later used by Andy.

As Andy goes alone to locate the UMA by tracking down Ruin, it turns out the UMA was sent out to "make friends" with Nico by showing him Ichico's soul and have him betray the Union. When Andy makes it back to the Union base, it turns out Nico had merged with Ghost to bring back his wife and the two fight. Despite Ghost improving his "Astral Dolls", Andy manages to break Nico by destroying his lab. This causes the UMA to completely take over the merging and enter Phase 2, being able to steal parts of Andy's soul with each attack. When Andy figures out a way to defeat it, it forces Fuuko next to its core to try and prevent Andy from killing it. This causes Nico to resist and eventually tear out Fuuko's soul from its body, allowing Andy to finish the two off. Dying, Ghost tries to eat Fuuko to regain its power, only to be held back Nico's recently deceased assistants and Ichico. It's remains are held up by Bau as it dies.

Union Arc
It's added as a punishment by Apocalypse for Fuuko opting to skip a Quest, with its existence causing the world to be altered. However, this allows Fuuko to save Ichico from her Unsleep by revealing that separating her soul from her body allows it to finally rest, and Ichico eventually beings using Astral Projection as a means of circumventing Unsleep.

Abilities
Phasing: Ghost can pass through solid matter, as shown when it departed the underground Union headquarters in order to reach the surface. Andy's attacks passed through it harmlessly. However Ghost is incapable of phasing through attacks performed by souls.

Flight: Ghost can levitate and fly at high speed.

Soul Storing: Ghost has the power to store souls.

Soul Severing: Ghost has the power to sever souls with a scythe.

Phase 2:

Trivia

 * Ghost ranked 70th in the Third Popularity Poll.