Confiésame is the command form of the verb confesar (to confess), with "me" attached, literally meaning "confess to me". It’s a powerful and intimate plea that you don't hear in every song.
In "Poema", the singer uses this word to passionately urge his love interest to admit her feelings, singing "Confiésame tu amor" (Confess your love to me). This single, dramatic word perfectly captures the romantic tension at the heart of the song.
Ready to jump out of the friend zone? That is exactly what Los Primos del Este are aiming for in "Poema". Over a modern corrido tumbado rhythm, the singer is tired of waiting around and just wants the truth: "Confiésame tu amor / Yo sé que me quieres / Sólo dilo para oírlo" ("Confess your love to me / I know you love me / Just say it so I can hear it"). He invites her out for drinks, calls her up on the phone (he uses the Spanglish slang "el fone"), and insists that since they talk all the time, she should not be shy: "Que no te de pena" ("Don't be embarrassed/shy"). It is a super direct, confident push to take things further.
The romantic compliments get pretty bold, too. He talks about how much he loves her waist ("cinturita") and clears his entire schedule just to write her this track: "Desocupé mi día pa' escribirte esta poesía" ("I cleared my day to write you this poetry"). While he knows she has trust issues ("Sé que tú no confías"), he tells her with total swagger that nobody else treats her like he will. It is fun, smooth, and full of everyday casual Spanish phrases you can use when you want someone to speak their mind without holding back.