Rascally Raccoon Spotted at Night

So, since moving into my new office things have gone really well. There is really just one downside. That is, there is a previous occupant.  He likes to clown around in the attic space above my desk, scratching himself and crawling around. I've been told by several people now that this occupant is a raccoon.

We've been trying to figure out how he gets in here and I think tonight we have a strong lead. My wife brought me dinner tonight and when she got in the car to head home she spotted Rascally Raccoon on the roof! He was walking along the roof and last she saw made his way over by the chimney. The chimney downstairs is blocked off, but somewhere there must be a way into the attic (nice chimney leakage). Anyway, here is a sketch I did of him on my Motorola Xoom Tablet. I have been wanting to do more with it to figure out the various art uses. This was done in Autodesk Sketchbook Mobile.