Ratboy is a character appearing in Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy and its anime adaptation. He is the biggest fan of the superhero Ratman.
Biography[]
Appearance[]
Ratboy is a little boy who wears a costume based on Ratman's own: A large blue rat mask that covers his whole head with a black visor for the eyes, a hole for the mouth, and a cape with a matching color. He also wears an orange dress shirt, olive green shorts held by a pair of black suspenders and buttons, peach socks, and brown shoes.
Personality[]
As Ratman's most loyal follower, he dresses like him and even calls himself "Ratboy" as if it were his sidekick.
Plot[]

Millionaires' Conspirancy[]
Case 7: Ratman Returns[]
Katrielle Layton, Ernest Greeves, and Sherl meet Ratboy when they first arrive to Bowlyn Hill. He delivers the group a letter with a threat to stop investigating, or they will disappear like Ratman. He says that a skinny man with a balloon-shaped head have him the letter, but Katrielle doesn't feel intimidated. Later on, Cesar Chance, Ratman's secret identity, forms a superhero team called "The Rat Pack" and Ratboy becomes a member of it.
Kat's Mystery-Solving Files[]
File 7: Ratman Returns[]
Ratboy plays a bigger role in the anime adaptation of this case. Here, he is a boy named Leo who requests the Layton Detective Agency to investigate Ratman's disappearance, as he thinks he's been kidnapped. In this version, Leo becomes Ratboy only after joining the Rat Pack.
Profile[]
Millionaires' Conspiracy[]

A young lad who was nutty about superheroes... and now he is one! He leads the 'Rat Pack' these days, keeping the streets of London safe. But he can only work when his mum says it's alright.
Trivia[]
- He is similar to Incrediboy from Disney-Pixar's film The Incredibles, as both are the biggest fans of a famous superhero, and name themselves after their hero but ending in "boy". However, Incrediboy ends up becoming a supervillain instead of a superhero.