watashi to tokyo: Rikishi seal

I picked up "weird sumo wrestler face seals" a few month ago. It a mystery someone put seal of two faces of sumo wrestlers everywhere in center of Tokyo. Actually I saw it a lot around my job at Roppongi. Now the mystery became famous as "Rikishi seal". This Japanese blog "Ginza-spy" has the details of Rikishi seal.

What?: The rikishi seal has some type, with frame or without frame. with some beige color or just white.

When? :It was said early 2008 it started.

Where? : Most seals are in Chuo, Taito, Koto wards and they tend to be close to the station. So we can guess IT will move by train.

Why?:On the Internet, people guess the purpose of this seal. And there were 7 widely-accepted theories.
1. Artist appeal their art.
2. It's major prank like BNE or counter plot to BNE.
3. Cult or some religion.
4. Yakuza's territory demonstration
5. Curse?

Who? : Who do this? On the Internet, An artist or an artist group called "QP" was said "they may be IT". This is the poster of QP's art event, I will agree it has the same "touch". But when we search about QP, we found another artist "Almond". This is almond's art. The top log art has Rikishi seal mood and this is almond's page of an art magazine! Hmm almond might be IT too. Actually in the Ginza area, there are some writing " アーモンド" (almond) near Rikishi seal, it is called "BOMB" that artists write their name near their arts on the streets.

But we can't say only almond do it cause QP and almond seem to have connection, there are their name on the same art magazine "Dumb Magazine" and like I wrote there are some variation in Rikishi seal. By the way, those kind of stuff is fun because it has mystery. we can leave it without finding IT.