What you're seeing on his suit is called "moiré" -- there are a lot of methods for removing it. I like to isolate the area and add a bit of a blur to it. Do a google search for After Effects and moire.
The term "Zebra" is used to describe the overlay that is sometimes used to indicate "out of legal" brightness or colors in a camera viewfinder (or similar places).
To avoid moire in the future, test wardrobe to make sure that it does not have a pattern to cause the moire'
In the meantime, it can be corrected using a low pass filter,, that removes the higher frequency detail from the image.
In after effects the "low pass" filter is also called FAST BLUR or GAUSSIAN BLUR. :)
To fix the moire, create an adjustment layers and add FAST BLUR, and adjust just high enough that the moire disappears. THEN use a mask on the adjustment layer to constrain the blur to the area needed.
You can also try a Remove Grain filter- it worked for me quite a few times. You will need to play with the settings a bit. Changing the frame from where the samples are taken and the way it affects solid areas will help.