The song titled 「FLAT」, opening theme for "Hamatora" (ハマトラ ) anime series, by Livetune ft. Yūki Ozaki.
Hamatora (ハマトラ) is a Japanese mixed-media project. The project began with a manga series written by Yukino Kitajima and Yūki Kodama as the character designer, while Yū Wazu is adapting the design to the illustration. The manga started serialization in Shueisha's Young Jump magazine in November 2013. An anime television series premiered on TV Tokyo on January 7, 2014 and a game titled Hamatora: Look at Smoking World developed by FuRyu will be released in Summer 2014. In the year 2014, select humans called Minimum Holders have been discovered to possess supernatural abilities. The series focuses on Mimimum Holders—Nice and Murasaki who form a detective agency called "Hamatora" based in the Nowhere Café in Yokohama.
"Minimum" - a special inborn power found in a limited number of human beings, known as "minimum holders." In Yokohama, the detective team Hamatora, formed by two minimum holders named Nice and Murasaki, comes across information connected to a serial killer being pursued by their old friend Art. It turns out all the victims are minimum holders like them. Unwillingly at first, the two detectives become involved in the investigation.