Set by the Japanese Association for Hair Research on this day because of the pun!
The pun: hair (of the head) in Japanese is read as touhatsu. In the hifumi numbering system, 10 is said as too/tou, and 20 as hatsu.Why—Cuttingup to this lineYoumu-chan got tangled into doing a hair examinationEeeeh!?
Why wouldn't it be good as it is!?