Jeque is the Spanish word for "sheikh", referring to an Arab leader, often one of great wealth and power.
In the song, Rels B creates a powerful image by singing, "Un jeque indigente" (A destitute sheikh). This is a stark contrast, used metaphorically to express that life without his love would make even the richest man in the world feel poor and empty. It's a unique and poetic way to emphasize just how priceless she is to him.
This song is a whole list of things that are useless or just plain wrong, and that's exactly what life is like without the person they're singing to. Rels B kicks it off with some wild comparisons: life without his person is like "Un jeque indigente" [a homeless sheikh] or "Un puchero sin sal" [a stew without salt]. It's a world where everything is missing its essential part. He sees her as a priceless work of art that can't be copied, saying anyone who tries to imitate her just ends up looking like a joke ("quedó en chiste").
Lía Kali's part adds another layer, looking back at how this person was her "ventana al mundo donde yo miraba" [window to the world where I looked]. But now, that connection is gone. She feels like the butterflies in her stomach "ya casi ni vuelan" [hardly fly anymore]. Both singers feel lost and adrift, asking where the other person is and how they can possibly be okay without them. The song perfectly describes that feeling when someone is so important that their absence makes the whole world feel broken and out of place.