This is Say Tevine. He is a Bokator instructor in Siem Reap. Bokator is possibly Cambodia's oldest martial art. It is a battlefield art, not a combat sport like kickboxing.
The art was almost lost during the 1970's as the Khmer Rogue sought to destroy all knowledge and practitioners of Bokator were killed.
More info here:
Lighting info: One bare speedlight at 1/4 on a German VAL.