Dr. Slump, Vol. 5 by Akira Toriyama

Robot girl hijinks from the creator of Dragon Ball!When goofy inventor Senbei Norimaki creates a precocious robot named Arale, his masterpiece turns out to be more than he bargained for!In a special dramatic episode of Dr. Slump, Senbei, Arale, and friends try their hand at law enforcement--with predictably hazardous results. And when Peasuke loses his heart to a tall sixth grader, Arale uses the Big-Small Ray Gun to make her small--so small that they lose her in the grass!
Binding: Paperback / softback