Ketsuekigata-kun!

is a Korean 4-panel webcomic by Park Dong Sung under the penname Real Crazy Man, an art teacher from Korea. The webcomic has been serialized on his blog. The comic has the theme of blood type personality classification. Japanese publisher Earth Star Entertainment later published the comic in book form and later a short anime adaptation by Japanese production house Assez Finaund Fabric. and Feel.

Plot
The anime adapted from the manga remake version of the Korean webtoon "A Simple Thinking about Bloodtypes" involving the faceless and nameless characters of four different blood types to discuss about popular anthropomorphized blood types (the stereotypes about the blood types) in Japan and Korea.