Say it in Red
Spoiler Alert!
This article contains spoilers for Umineko: When They Cry - Question Arcs. Proceed with caution.
In Umineko, the "Red Truth" is a fact given in the game that is always true, regardless of evidence. It is called the Red Truth because it is always presented in red text. Eventually, people in twitch chat started saying "Say it in red" whenever Joe said something that chat thought might either be untrue or wanted concrete evidence of. Joe will usually respond by saying "I refuse" or by repeating the sentence.