Question about the Mesmer Skill "Shame"

Shame:
"For 4-9 seconds, the next time target foe casts a spell on an ally, the spell fails and you steal 5-12 Energy from that foe, and Shame ends."

Now my question is, does ally in this situation mean my ally or any ally of the foe I am casting shame on? So would Shame trigger on him casting healing breeze on one of his allies or when he casts firestorm on me?

Means your target's ally, and you steal energy from the person you cast Shame on.

You Target an enemy, and when that enemy cast a spell on an ally the spell fail and you steal energy.