Seki continues to goof off, and Yokoi continues to watch him and occasionally try to thwart him. In this volume, Yokoi has to borrow Seki's Social Studies textbook and learns that
he edited it to tell the story of a master thief. Also, Seki mends stuffed animals (by cannibalizing a less-cute one), creates a foosball table out of his desk, sets up an ant farm in his bag, creates an airstrip for paper airplanes in the corner of the classroom, practises good table manners, and brings his sister to class. Oh, and there's a fake bomb and an Earth made out of eraser shavings.
There are zero new developments as far as characters and character relationships go. Goto still thinks Yokoi is under Seki's thrall, and Seki's sister still desperately wants to play with him while he resists and ignores her.
My favorite thing in this volume was the edited textbook. It was really cleverly done and something that I could imagine a bored kid doing in real life.
(Original review posted on A Library Girl's Familiar Diversions.)