Q: "Torture" allows the caster to place -1/-1 counters on a target creature. If the "Torture" enchantment is removed, are the -1/-1 counters also removed, or do they remain on the creature? If the -1/-1 counters reduce the target creatures toughness to 0, is that creature destroyed?

A: -1/-1 counters are put on the creature, so they stay even if Torture goes away. A creature with a toughness of 0 is destroyed and put into the graveyard.