Pitorro is the name for a traditional Puerto Rican distilled spirit, essentially a type of moonshine. It's often homemade and famously strong, sometimes flavored with fruits like coconut (coco), as mentioned in the song.
In "PIToRRO DE COCO", Bad Bunny creates a powerful image of heartbreak. His grandfather gave him the pitorro to celebrate the holidays, but instead, he's drinking it alone while crying over a lost love. This word is central to the song's melancholic and culturally rich story.
This song is a perfect holiday heartbreak anthem. Bad Bunny kicks off the New Year feeling completely miserable because the person he loves isn't there. He remembers last year when everything was different, when her "primer abrazo" [first hug] of the year was just for him. He was "en las nubes" [in the clouds], but then he fell hard, "como un rayo" [like a lightning bolt]. Now, there are no calls, no texts, just silence.
To cope, he's drinking "pitorro de coco", a strong Puerto Rican rum his grandfather gave him for celebrating, not for crying over someone at midnight. His friends are making fun of him, but he can't help it. He knows she's bad for him, admitting "Siempre supe que eras mala" [I always knew you were bad], but he'd just close his eyes and kiss her anyway. He even uses a great dominoes metaphor, saying she blocked him in the game with a double-six and a double-five. It's a classic Bad Bunny mix of sad feelings and very specific, local details.