Is there a cloakroom?
Pllek has an (unguarded) coat rack where you can put your coat. Of course, you are also free to take your coat and bag into the venue. There are also paid lockers at Pllek. You can rent them for €2. Bring a coin for this, but bear in mind that you will lose it when you open the locker again. These lockers are too small to hold a laptop.