Day 7: Did you get your most prized Pokémon yourself or did you trade for it?
It's hard to choose a most prize Pokemon, but I'm gonna go with a shiny Charizard that I masuda'd back in 2014 in XY. It didn't take very long to get it and it was Modest with its Hidden Ability, and an incredible IV spread of 31/0/31/31/31/31. Couldn't have been any better. I nicknamed him Rexflame.
Day 8: How do you organize your PC boxes? Do you change the wallpapers?
I have egg boxes with the Pokemons name as the title, so for example a box named "Bulbasaur" with a bunch of perfect IV/HA Bulbasaur eggs waiting to be SV hatched. I have a box of "Utility" pokemon - dittos, HM slaves, contest slaves, nature synchs, etc. I have several boxes of "parents" that I use for breeding. And I have boxes of shinies, perfect shinies, Pokemon for trade, trained Pokemon I use for battling. All of the boxes backgrounds match either the pokemons type or the theme of the box.