Redditor emzieees has let her downstairs neighbours borrow her printer "a couple of times" for essays.
Which meant when the 19-year-old from California heard it whir into life up on Monday, she wasn't expecting this to come out.
Emzieees shares wifi with the people who live below her, which meant it was easy for them to deliver the, um, friendly note.
But she tells i100.co.uk they got the wrong end of the stick:
I wasn't actually sleeping with anyone, I was trying a new workout routine. Apparently sweating through Day 3 of Insanity upset my neighbours.