Placosón is a slang term, especially common in Mexican Spanish, used to describe someone or something flashy, ostentatious, or openly showing off wealth and status.
In "Como mariposa abre las puertas, placosón se deja ver" ("Its doors open like a butterfly, real flashy to show off"), the word describes a car designed purely to be noticed, flaunting luxury for everyone to see.
This song paints a picture of a luxurious and successful lifestyle, giving a shout-out to a friend the singer calls "El Capi" (The Captain). The lyrics describe someone who enjoys the best things in life, from flying in private jets with friends to driving a Tesla with impressive "butterfly" doors. This person is always dressed to impress, with clothes and shoes that "shine" wherever they go.
Beyond just the material wealth, the song highlights a life of influence and high status. The narrator mentions getting front-row seats at the most exclusive events and partying with famous people like J Balvin and Maradona. Despite this flashy life, "El Capi" is also described as smart and strategic, keeping a "low profile" to get ahead and always being "three steps" ahead of everyone else. It's a celebration of living large, looking fresh, and being at the top of your game.