Wahoo with Fresh Grapefruit Sauce

2 large ruby red grapefruit with sections
2/3 cup sugar
1/4 cup white wine
2 cups fresh squeezed grapefruit juice
1/4 cup water
2 tablespoons cornstarch
6 7 ounce steak cut filets of Wahoo, broiled until just done

Peel grapefruit. With a paring knife, lift out grapefruit from each
segment taking care to leave behind the skin. Squeeze the juice from the
remaining pulp and set the juice aside. Reserve the grapefruit sections
for the garnish. Heat sugar in a saucepan until caramelized and add wine
and grapefruit juice Simmer until sugar is incorporated. Mix water and
cornstarch together, use mixture to lighten sauce and drizzle over grilled
wahoo. Garnish and serve.