The bud blossomed into her ear, its hairlike tendrils snaking towards her eardrum where they fanned out into electric petals, sensors cool against her hot skin. The soft thud reminded Meredith of being submerged, and in a way, she was: holding her breath against the summer rush hour stench of body odor and urine as the subway undertow pulled her beneath the island. The bud measured her heart rate, body temperature, slight changes in her pH. It understood her mood, and it provided a soundtrack to match. Slow, quiet. A Monday evening mix.

Meredith was well into the third track when her hardware buzzed against her thigh. She shifted her weight to detach it, and pressed the backlight button to better make out the words. Josh.

u ok?

im fine, she messaged back. y?

Three thousand miles away, on the west coast, the boy Meredith had met on her favorite band’s forum frowned at the letters on his own messenger. She couldn’t lie to him any more than she could lie to her bud. Josh syndicated all of his friends’ iTracks, and the downtempo music broadcast her mood better than any facial expression could.

im reading ur itrack, he typed. sounds sad.

just a mellow monday, Meredith replied.

want company?

Meredith answered with an indifferent emoticon, but Josh understood. He positioned his analogue headset over his ears and smiled at its weight, at the cold feeling of leather-covered foam beside his cheekbones. He clicked the link on her iTrack feed and jumped in mid-song, then settled back into his armchair, closing his eyes and concentrating on the gentle, melancholy notes.

Separated by an ocean of land, Meredith leaned into the hard cradle of an orange subway chair as her world, too, faded to music. Around her, dozens of bodies shifted to their own rhythms, composing their iTracks over the steady, low hum of the train.