Master Keaton Vol 2

From the VIZ Media edition

Taichi Hiraga Keaton has a degree from the University of Oxford's master's programme in archaeology, but he abandoned further studies due to tight finances. Because combat didn't suit his nature, he left the SAS and is now an exceptional insurance investigator. Equipped with a strong body and a keen intellect, Keaton is about to solve the most difficult cases ever seen!

Source: Anime News Network Encyclopedia