Japanese version >> Marine Corps Yumi #64
First day on the job is usually mundane, and mostly just doing paperwork and such to inprocess/check in. And every Marine has a colorful war story or two up their sleeves, esp. if they deployed.
NBC/NBCD = Nuclear, Biological, Chemical Defense. Also called CBRN/CBRNE (Chemical, Biological, Radiation, Nuclear, Explosive.)
OIC = Officer In Charge. Basically, the senior officer in a section/unit who serves as the boss.
CWO-3 = Chief Warrant Officer 3. We pinned his rank diagonally/vertically vice horizontally as a fictional tweak. Thanks for noticing, eagle eyes.