Master Keaton, Vol. 4 by Naoki Urasawa

Taichi Hiraga Keaton is an insurance investigator educated in archaeology and trained in SAS survival combat who's about to take on the world, one case at a time!

Taichi Hiraga Keaton, the son of a Japanese zoologist and an English noblewoman, is an insurance investigator known for his successful and unorthodox methods of investigation. Educated in archaeology and a former member of the SAS, Master Keaton uses his knowledge and combat training to uncover buried secrets, thwart would-be villains, and pursue the truth...

Taichi Hiraga Keaton's dream is to devote his time to further studying archaeology. In reality, however, he is an ace investigator for the insurance organization Lloyd's. A kindhearted man, Keaton has a life filled with danger and setbacks due to his job and calling.