If you want an easy-to-understand, fast-paced plot; look elsewhere. Gogo Monster follows elementary schooler Tachibana as he is ostracized from his class due to acting out over creatures that only he can see. The readers are shown his delusions and there are many panels which focus on the ambiance, which adds to the surrealist tone.
There are only a few characters, but they're pretty well fleshed-out, and you can understand the way they think very well by the end.
The artstyle is a little rough, but surprisingly detailed. It really matches up well with the main character's doodles of what he sees.
There's only a few chapters,
but each chapter is very long, in the order of 90 pages. It took me about 2 hours to read in total.