Pound Years
When a seemingly heavier person no longer refers to when an event took place using normal times, but instead makes this clear according to their weight at said time.
Person 1: "Dude, that concert was forever ago!"
Person 2: "Yeah, almost 20lbs ago..."
Person 1: "Since when do you talk in pound years?"
Person 2: "Yeah, almost 20lbs ago..."
Person 1: "Since when do you talk in pound years?"