Intereses translates to "interest," as in the fee you pay on a loan. This word is the key to the song's clever central metaphor and title, "El Préstamo" (The Loan).
Maluma sings that he only lent his heart, he didn't give it away. He cheekily warns his lover, "Ojalá no olvides de pagar los intereses" (I hope you don't forget to pay the interest), implying his affection isn't free and requires her continued effort and attention.
El Préstamo turns love into a business deal, and Maluma is the savvy yet wounded banker. Over an infectious reggaeton beat, the Colombian superstar tells his partner that his corazón was never a gift - it was only on loan. He keeps repeating "yo no lo di, yo lo presté" to underline that he expects his feelings back with interest. The playful metaphor hides real vulnerability: past heartbreaks have made him cautious, so he speaks upfront about limits, payments, and emotional late fees.
Between confident swagger and honest confession, the song explores modern relationships where affection can feel transactional. Maluma warns his lover that if she will not honor the "loan agreement," plenty of other suitors are waiting in line. The result is a catchy mix of flirtation, financial imagery, and raw transparency that invites listeners to dance while thinking twice about how they invest their hearts.