Fixation. Fetish. Call it what you will, there’s something percolating in the fast-food liquid zeitgeist with McDonald’s Diet Coke.

Since its debut in the early 1980s, Diet Coke has enjoyed a large following, with some fans guzzling gallons each day, for better or for worse. Recently, however, a very specific form of this beloved low-calorie beverage has taken over social media, namely that vended by McDonald’s soda fountains. TikTokers are uniting over its ability to create a uniquely “peaceful” Diet Coke moment, with many claiming Diet Coke is a necessary part of their self-care routines.

For some, this fascination can rapidly devolve into a dangerous obsession.

“It started innocent,” explained Doug E. Fresca, of Dover-Foxcroft, Maine, who notes the irony in his name. “A quick large Diet Coke from McDonald’s on my lunch break. … That golden ratio of syrup to carbonation to slightly-too-much-ice. But then … I spiraled. At my lowest, I pulled up to the window, handed them dirty bills I begged for on the street, [and] ashamed, I whispered: ‘Make it extra cold. You know what I need.’”

Public relations executive Dutch Small of Mexico City recounts similar chronic struggles (victories?): “Let’s just say if McDonald’s ever starts a loyalty program based on Diet Coke consumption, I’ll be their first platinum member. I don’t drink it every day … just every day that ends in ‘y.’ It’s the life-revival infusion you can’t live without, like the deserts miss the rain, especially first thing in the morning with a McMuffin.”