No band right now does existential dread and doomed romantic melodrama better or with more blown-out, explosive glee than Welsh tweecore septet Los Campesinos! Over three ace albums in as many years, the band has grown from clever and kinetic kids' games into darker (but never humorless) lyrical themes and more fully realized instrumental disarray. Their new album, Romance Is Boring, is a thrilling mess of sharp hooks and sharper wit, huge sing-along choruses clashing with jarring guitars, heaving brass, and restless rhythm. If you're not a hormone-drunk teenager, their live show will make you feel like one again. (Showbox at the Market, 1426 First Ave, 628-3151. 8 pm, $17.50 adv/$20 DOS, all ages.)