Frankly, i randomly found this while looking for a scientific anime. To be honest, I didn't expect anything before I started, but as you watch it, you can understand that it is very entertaining and interesting. If I were a biology teacher, I would definitely make my students watch it. Don't expect too much in terms of action and coolness. However, if you are looking for funny and comfort anime, this will do the job. I really liked the events mentioned (I mean the events in the body) and the reactions of the characters. It has become one of my favorite short anime.