血液型くん!

"A Simple Thinking About Blood Type" (Ketsuekigata-kun!) is a South Korean 4-panel webtoon created by Real Crazy Man, focusing on blood type personality classification. Initially serialized as a webcomic, it was later published in book form in Japan and adapted into a short anime series. The story features anthropomorphic blood type characters, exploring popular stereotypes about blood types in Japan and Korea. The anime characters are designed with a simple, two-dimensional style, distinguished by blood type symbols on masks and differentiated by color and hairstyles for gender and character traits. The anime aired four seasons between 2013 and 2016. The work presents the personality characteristics of different blood types in a lighthearted and humorous way, gaining popularity in Asia. The voice actors in the anime also share the same blood types as their respective characters.