What's Michael follows the adventures of a ginger tabby called Michael. The stories often change setting: in one, Michael may be owned by a young Japanese couple; in the next, Michael may be owned by an older couple with children and in a third, Michael might be owned by a yakuza. There are even story settings that place groups of cats in business suits or playing baseball in sport team uniforms.
What's Michael? was partially published in English by Dark Horse from April 1, 1997 to May 10, 2006. It was also regularly featured in Dark Horse's manga anthology Super Manga Blast from March 29, 2000 (issue #1) to February 1, 2006 (issue #59, final issue), as well as sporadically in the educational publication Mangajin, from June 1990 (issue #1) to September 1997 (issue #68).