It’s no surprise that “PARTYGIRL” is the name Charli xcx adopted for the DJ nights she put on in support of BRAT. It’s kind of her brand anyway, but on her sixth studio album, the British pop star is reveling in the trashy, sugary glitz of the club. BRAT is a record that brings to life the pleasure of colorful, sticky dance floors and too-sweet alcopops lingering in the back of your mouth, fizzing with volatility, possibility, and strutting vanity (“I’ll always be the one,” she sneers deliciously on the A. G. Cook- and Cirkut-produced opening track “360”).