Fließend Scheiße literally translates to "fluent in shit" or "fluent in bullshit." It's a highly colloquial and provocative phrase that immediately grabs attention.
In the context of the song, it's used to describe someone who speaks an incredible amount of nonsense or lies with great ease and confidence. The artists embrace this idea, suggesting that speaking "Scheiße" is an art form for them, making it a memorable and unique expression.
"Fließend Scheiße" ("Fluent Sh*t") is 257ers' tongue-in-cheek take on a certain kind of person: someone who sounds impressively deep and articulate, but is actually just talking nonsense with total confidence.
The song plays with a contradiction. The woman he's singing about seems thoughtful, quiet, and into serious conversation. But the narrator keeps insisting that what actually comes out of her mouth is garbage, just dressed up to sound smart. It's less an insult than a strange kind of affection: he likes her anyway, maybe even because of it.
Musically and lyrically it's classic 257ers: crude, funny, and unapologetically silly, built on a repeated hook that turns "speaking fluent bullsh*t" into an almost tender catchphrase.