Greña is a colloquial term for messy, tangled hair, or even dreadlocks. It's a vivid and somewhat informal word that adds a lot of character to the lyrics.
In the context of the song, Rochy RD uses it to describe people who are envious or have a negative attitude, possibly implying their unkempt appearance reflects their chaotic or envious nature. It's a word that paints a picture and is quite unique to hear in a song, making it memorable.
Rochy RD and Skary Movies bring the heat in "Bobo De Verdad," a track all about staying true to yourself and your hustle, no matter what. They're basically telling everyone to mind their own business because they're on a different level. Rochy talks about how his success makes others jealous, saying "que se me nota el brillo llaman en mi cuello y los de lillo se llenan de odio" [that the shine on my neck is noticeable and the jealous ones fill with hate]. He's been through a lot, coming from "la dificultad" [difficulty], and he's not about to stop now.
This song is a real anthem for anyone who's ever felt underestimated. Rochy and Skary Movies are confident in their path, even if others don't understand it. They're not looking for trouble, but they're not afraid of it either, warning "tú no sabes lo que vamos de verdad" [you don't know what we're really about]. It's a reminder to focus on your own journey and let your success speak for itself, just like they do!