Jangueal is a Spanglish verb derived from the English phrase "to hang out." It's commonly used in Puerto Rican and Caribbean Spanish slang to mean to hang out, party, or chill.
In the song, Cauty repeatedly asks, "Tírame después de jangueal" (Hit me up after you hang out/party), indicating a casual invitation to meet up after a social gathering. This word is interesting because it's a clear example of linguistic blending and is very characteristic of modern urban Latin music.
Cauty's "DESPUÉS DE JANGUEAL" is all about that late-night craving for someone special after you've been out with friends. He's chilling, maybe a little high, and suddenly, he's got this intense urge to see her. He texts her, even if it might cause some drama, asking, "Cuando nos vamos a ver, Cuando vamos a bellaquear?" [When are we going to see each other? When are we going to make love?].
He's pretty direct, telling her, "Si no tienes na' que hacer, Llégale después de jangueal" [If you have nothing to do, come over after you hang out]. Cauty is totally smitten, admitting, "Me tienes enchula'o" [You have me in love]. He remembers their past, even from school, and how she activates him "como el perico" [like cocaine]. It's a fun, no-holds-barred look at that impulsive desire to connect with someone when the night is winding down.