Tonight on Late Night With Seth Meyers, Lena Dunham joined pop songwriter extraordinaire Sia for a performance of “Chandelier.†While the singer lay face down in a bunk bed, a blonde wigged Dunham acted as her lip-syncing proxy, spinning around in circles like a maniac, smashing stuff, and playing with toilet paper before eventually crawling into bed for a spooning session. We’ve got to hand it to her: While Dunham may lack Maddie Ziegler’s classical dance training, she’s certainly not afraid to commit.