Sebastian Castellanos (voiced in Japanese by Hiroyuki Kinoshita, and in English by Anson Mount, in the first game) is the main character of the horror game The Evil Within/Psycho Break.
With a large amount of tragedies in his life prior to the start of the game, he struggles with severe depression and alcoholism, leaving himself prone to mental strain. This leads him to be very easy to pull in to the STEM connection, along with Leslie, Kidman, and Joseph.
As a detective with the KCPD, Sebastian wears a pretty standard outfit, a grey striped vest over a white button-up shirt, accented with a red tie, shoulder holsters for his gun, a tactical belt to carry the rest of his necessities such as a lantern, brown jeans, and black lace up shoes. For his hair I had a bit of difficulty finding an exact match for shade in the wig style, but if you have short, darker hair, it should be easy to just smooth it back as he does.