Ketchup Mania's hardest album to date takes the punk-pop template handed down from Green Day or Blink 182, fusing it with the darker, metal-brushed sound of U.K. band The Wildhearts and poppy female vocals that recall 1990s J-pop giants Judy & Mary. The result is a multicultural paean to rock 'n' roll excess, an aural bloodbath that'll leave your ears sticky.

The band's live show offers some of the wildest moshpits you'll ever see, while their music regularly scales the charts — an imbalance that mirrors their blend of heavy riffs and overtly cutesy vocals, a combination of light and dark that makes them intriguing.

Recent single "Bad! Bad! Bad!" is a pileup of tight rhythm, chunky guitar and saccharine-sweet vocals, as an offbeat melody burrows into the psyche. On "Everlone," Hiro's voice is manglarized through a vocoder with spine-chilling effect, as the band plunge into the sort of pyrotechnic metal usually pedaled by bands such as Avenged Sevenfold. The singalong chorus to "Just a Mess!" is pure pop, complete with Abba-esque backing vocals, while "Pink Water" punctuates a head-down rock-out with a few bars of Avex-style Eurobeat synth craziness.

This playful flirtation with roaring riffs and fun melodies results in an album of surprising depth, from a band that seems not to take itself too seriously while always operating with defined intent. "F.L.A.G" takes all notion of punk-genre rules and sticks it up your jacksie — and you can't ask for much more than that.