All right! We finally have information on the new RADWIMPS single now, and it's a lot of information that I like. Firstly, the single is a Double A-side that's titled "Gogatsu no Hae (Flies of May) / Last Virgin" and also includes a third track titled Nipponpon, which is by RADWIMPS' alter-ego "The Miso Soups" (first time they've done a track as them in 7 years).
Most importantly: There is a limited 24 hour period going on right now where you can get an official download of the first A-side, "Gogatsu no Hae". It's a great song, so I recommend that you take advantage of the chance and grab it while you can.
Here it is: http://radwimps.jp/gogatsunohae/
Lastly, there are two different, but equally nice pieces of cover art for the new single, while I'll show below.