What is pantsu and why this club is named pantsu?
Well I think it is best described in wikipedia:
"In most modern cultures, panties have become a bit of a cultural icon describing sexual mischief and a fun way of life, especially for high school and college age girls who are more likely to enjoy them than the woman who grows up wearing granny panties. In Japan, panties (pantsu) are commonly depicted as being a highly flirtatious, naughty element to a female's persona." (Wikipedia, Panties article) Moto:
Pantsu - the only word in color. Purpose:
To establish (naughty) community interested in pantsu within MAL. Within which community members could share their naugtiness without being punished, laughed at.