What kind of title is this?: Manga.
Where can I read it?: Reading links are listed for VIZ, Shonen Jump Plus, Naver Series, Official Site. Check availability in your region.

Synopsis

About Moriarty the Patriot

In the late 19th century, Great Britain rules over a quarter of the world. Nobles sit in their fancy homes in comfort and luxury, while the working class slaves away at their jobs. When young Albert James Moriarty’s upper-class family adopts two lower-class orphans, the cruelty the boys experience at his family’s hands cements Albert’s hatred of the nobility he was born into. He asks the older of the two boys—who has a genius mind and a killer instinct—to help him rid the world of evil, starting with Albert’s own family! (Source: VIZ Media)

Mystery Psychological Thriller