Zook is a rock gnome, standing around 3' tall. He wears common clothes with a backpack, but he carries a thick hardcover book with him at all times, along with what appears to be a twig.
'Ello! I have loads of names, but the Guild knows me as Zook Wizblock Peppernickle (you can call me Zook, Wizblock, Wiz, Block, or anything else that strikes your fancy). I, uh, study the applications of magic, you might say. I used to think I wanted to be a sage, so I left my home to head off and try to find a mentor. On the way there, though, I was attacked, well and true, by a bear! Well, I panicked and threw up a Shield, and it worked! Really made me think about how relatively impractical all my studies were, and more importantly how practical they could be if a refocused. So I spent a while wandering around, helping people here and there, until I made a little bit of a name for myself. Someone reccommended I join the Guild, and I figured it'd be a good way to practice and to help people out, so here I am!
Despite his childlike name, demeanor, and curiosity about the world, you've learned over your year of knowing Zook not to underestimate the breadth of his knowledge. He spends most of his time either studying his spells or trying to find people to nerd out with over magic - the rest he spends relaxing, playing lighthearted pranks, and listening to other people talk about their passions, whatever those may be. He helps out around the guild identifying magic items, as well, and you can tell when he's doing so by his cries of "Oh! Coooooool!"