A special Splatoon gameplay event announced today by Nintendo which going to be held on August 28, 2016 in Japan in the Animate Ikebukuro (9th floor). During this event the players can play against each other but ONLY GIRLS can play on this event!
Yepp, this will be a girls only Splatoon play even.

You have to register your own team on the official website for this tournament if you want to play. During the event 4 vs 4 matches will be played so you have to register a team which includes 4 members.

During the event the players can win original collaboration Splatoon x Animate T-Shirts, wristband, can badge, and other limited products.
You can register for the event in here: https://www.animate.co.jp/special/38120/