What is rappers in blue?

As an AI language model, I do not have personal beliefs, but as far as I know, "rappers in blue" does not refer to a particular group or style of rappers. It could be interpreted in different ways, such as rappers who wear blue, rappers who are associated with the color blue, or rappers who use "blue" lyrics (related to sadness or melancholy). There are many rappers who wear blue as part of their clothing style or image, but this is not necessarily indicative of their music genre or message. Similarly, some rappers use the color blue in their album art, stage design, or merchandise, but this is mostly a stylistic choice rather than a defining characteristic. As for "blue" lyrics, there are some rap songs that deal with themes of depression, heartbreak, or social injustice, which could be considered "blue" in a metaphorical sense. However, this does not apply to all rappers or all rap songs. Ultimately, the term "rappers in blue" is too vague to provide a specific answer without further context or clarification.