When I first moved to New York after a year in Seoul, I missed the thick, black-haired crowds, which looked from space, I imagined, like the bundled heads of inked-up brushes. I was saved from my longing by the express B/D train, which ran in a blink from my West Village apartment to Chinatown’s Grand Street, ersatz Seoul. I’d buy rice cakes and fresh tofu from a street vendor, and vegetables from a shop that stuffed my greens into bright, red-orange plastic bags.

From my second apartment in Bushwick, Brooklyn, I often rode a Miyata 10-speed to Manhattan, taking in a westerly view from the Williamsburg Bridge. The down-ramp would land me right in the honking crush of Lower East Side traffic, which I often cursed but would sorely miss if I ever left.

These days I’m mostly in Chinatown and the Lower East Side to meet with workers and organizers at the Chinese Staff and Workers’ Association and the National Mobilization Against Sweatshops. My day job is working as a lawyer for low-wage laborers, like the women who paint your nails or the guys who mince garlic for your overpriced pasta or underpriced lo mein.

I’d gotten used to taking the J train from my office in the Financial District to the Essex Street stop, when my friend introduced me to the M15 bus—a minor revelation. The M15 shoots up and down the eastern edge of Manhattan, from Battery Park City to El Barrio. Since the MTA added the express “Select Bus Service” variation, it’s been even easier to track the M15’s segmented ridership: Fulton Street’s office workers, Catherine Street’s Asian grandmas, and hipsters on Grand up through Houston.

As a Brooklyn commuter, bus-riding is a temporary reprieve from life as a mole. And the M15, in its twist-turning, northward path to the stable, perpendicular grid above Houston, is hands-down my favorite. It’s on the M15 that I chatted with the house keyboardist for an Atlantic City casino, an older white guy with a blurry G-clef hand tattoo. Another time, I made the mistake of asking a loud-talking fellow passenger to keep it down—I had to disembark prematurely, halfway through her inventive list of Spanish synonyms for chink.

Some nights after work, I take the M15 for fun and jot down the conversations I hear, the things I see. “Why you gotta pick a bus that smells like shit?” a teenager recently yelled at his friend. As we drove up Allen Street, I spotted a homeless man and a recycling collector pulling their massive carts unintentionally in tandem. Near Grand, a Hasidic grandfather with one eye was eating an ice cream sandwich and gabbing on his phone.

“Next stop, Houston Street,” the driver intoned over the intercom. We had reached the upper edge of the Lower East Side and the end of another trip for me.