NC - YAY! I was born in Kinston and grew up in Taylorsville. I'm a Tar Heel too.
Job shadowing is following a certain employee for a day or even a week or two to see what he does as part of his job. I work as a cataloger in a library and have been shadowed by high schoolers who are thinking about a library career or by adults who want to switch careers. I usually put them to work doing various parts of my job so they can get a real feel for what cataloging entails.
You'd have to find a manga artist in your area, contact him or her, and get permission to hang out with him/her while at work on manga art.
Everything these days seems to be on the Internet, so I went to YouTube and put "manga artist" in the search box. I got this nifty video (with a musical background!!) and with others recommended along the side of the video box.
YouTube - Manga Artist @ Work - Sketch