Lyric discussion by The One Free Man 

Cover art for La Chispa Adecuada lyrics by Héroes del Silencio

The lyrics for English speakers:

The words were wasps and the streets were like dunes and I'm expecting your arrival. In a coffin I guard your touch and a crown, with your hair tangled wishing to find an infinite rainbow. My hands that are still bones and your belly that tastes like bread, the cathedral is your body. Your were summer and a thousand torments, me a lion who smiles at the walls which I've repainted in the same colour.

I can't distinguish between kisses and putting down roots. I can't distinguish between the complex and the simple. And you are now on my list of promises to forget everything burns if you use the right spark.

The fire that was sometimes your own, but the ashes were always another's white sperm sliding through the spine. We are already much older and more honest, but so what if we look upon the "lagoon" that is called eternal absence.

I can't distinguish between kisses and putting down roots. I can't distinguish between the complex and the simple. And you are now on my list of promises to forget everything burns if you use the right spark.

Seems to me like the speaker is breaking off a relationship, but looking over the comments, there appears to be quite a bit of disagreement over the meaning.