Contravía literally means "against the flow of traffic" or "the wrong way" on a one-way street. It's a fantastic and visual word that you don't hear often.
In this song, the singer laments, "No vi la señal de que iba en contravía" (I didn't see the sign that I was going the wrong way). He uses it as a metaphor for a relationship doomed from the start, perfectly capturing the feeling of realizing you were heading straight for heartbreak.
Have you ever loved someone who seemed totally unfazed while you were falling apart? That is the whole mood of "Frágil" by Yahritza Y Su Esencia and Grupo Frontera. Right from the start, the singer takes the blame for diving in headfirst, singing "metí el corazón en donde no debía" ("I put my heart where I shouldn't have"). There is a clever driving metaphor here too: "iba en contravía" literally means driving the wrong way down a one-way street, but here it describes walking straight into disaster without noticing the warning signs.
The real punch comes in the chorus, where the singer wonders why they got stuck with an easily breakable heart while the other person seems completely cold. The lyric "el que me tocó a mí es frágil, por eso lo rompiste fácil" ("the one I ended up with is fragile, that's why you broke it easily") sets up a painful wish to be "sin sentimientos" ("without feelings"). It is a super direct, bitter track about watching someone move on without a scratch while you are stuck remembering every single moment.