Cora is a popular slang term for corazón, meaning 'heart'. It's frequently used in modern Regional Mexican and urban Latin music to add a more personal and informal touch.
In this song, Junior H sings "El cora que te regalé" (The heart that I gave you as a gift), using this casual term to express a deep, raw feeling of heartbreak. Learning 'cora' gives you a taste of the real, everyday language you'll hear in today's music.
Junior H is going through it in this song. He's been dumped, and he has no idea why. One minute, he thought everything was fine—she even "Me dio un beso y se marchó" (Gave me a kiss and left). The next, he realizes she's gone for good, leaving him completely confused. He sings that she just drifted away from him, and he stopped getting messages. The most brutal detail? He says, "El cora que te regalé / Lo dejaste en mi casa" (The heart I gave you / You left it at my house). She didn't even want the gift that represented his love.
So, what's he doing about it? Crying. A lot. The title itself means "And I Cry." He's trying to pretend it doesn't hurt, but he admits he feels incredibly lonely and even begs at night for her to come back. He's also drinking to cope, but it's not really working. He's just left trying to hold back his tears, "Haciendo como que no duele tanto" (Pretending it doesn't hurt so much).