Matt newbie

So, I'm thinking of apping a Matt, which is scary for me, because I've never played him before (I'm usually a Misa Rper), so changing to a different character, esp. one as controversial as Matt can be, demanded that I seek out some help in this. I want to do him justice, especially because some of the other DN rpers there are ones I respect and want to give them the best Matt I can.

I've already looked at some of the past discussions here, which already have helped me out tons in figuring out his personality. Now, I have a question regarding his history. What do you all suppose he did when Mello left Wammy's House?