Placoso is a slang term, particularly used in some regions of Mexico, to describe someone who looks tough, intimidating, or like a gangster. It implies a certain street credibility or a menacing appearance.
In the context of
"El Chinito (Version Tololoche)" is a corrido about a young man from Southern California nicknamed "El Chinito" (also called "El Gordito" or "El Sobrino"), known for his sleepy, half-closed eyes from smoking marijuana. Set to a tololoche (upright bass) arrangement, the song traces his life from roaming the streets as a kid to finding his footing after moving north, now recognized for his nice cars and easygoing lifestyle. Throughout, it celebrates rolling and smoking marijuana as a constant ritual, naming different strains and forms. Near the end he says goodbye content, dedicating the song to his late father, who he says still watches over him from above.