Ah... Reading the commentary, the image is reflecting on the recent and popular Japanese concept of "Cool Biz" Which is the idea of dressing down for work (not wearing a suit jacket & tie, etc) in order to physically keep cool and prevent businesses from wasting energy on A/C. The author is saying he likes the trend of people wearing less clothes to work (Youmu seems to have taken it to an extreme).
I guess Myon is Mickey to demonstrate his? commitment to dress down in the only way he can. Wearing a Mickey t-shirt to work might also be a bit extreme though at a Japanese workplace, "Cool Biz" or no.