Nothing to hide
Sanja Matsuri, in Senso-ji, in the quarter of Asakusa, in Tokyo, is one of the biggest festivals in Tokyo.
The festival as such, well, it's nothing too special if you've seen others. It is particular, though, by how Yakuza show off their status in the clear.
I cannot find an authoritative source for this, but apparently Yakuza are not supposed/allowed to show off their tatoos (how do you pass a law that forbids the public display of tatoos, beats me).
Only (supposedly) in the Sanja Matsuri, not only they do not hide themselves, but become a full-fledged showcase of art on flesh.