In a saucepan over medium heat, sauté the garlic, and 2 tablespoons of the parsley in 2 tablespoons of the olive oil, stirring once or twice, until the garlic is fragrant, 1 to 2 minutes. Add the shrimp, salt, and pepper and cook, stirring just until the shrimp are pink, about 2 minutes.

Using a slotted spoon, transfer the shrimp to a plate. Add the stock to the pan and bring barely to a simmer. In a large saucepan over medium heat, sauté the onion in 3 tablespoons of the oil until tender, about 5 minutes. Add the rice and cook, stirring, until hot and coated with the oil, about 2 minutes. Add the wine and continue to cook, stirring often, until the liquid is absorbed.

Add 1/2 cup of the stock and cook, stirring constantly, until the liquid is absorbed. Continue add the the stock, 1/2 cup at a time, always waiting for each addition to be absorbed before adding more. When the rice is about half cooked, stir in the tomato, salt, and pepper. The risotto is done when the rice grains are creamy on the outside and firm, yet tender to the bite, 20 to 25 minutes total. Rice varies, so you may not need all of the stock, or you may need a little more; if so, make sure it is hot.

Stir in the shrimp and crabmeat and cook, stirring, just until heated through, about 2 minutes. Taste and adjust the seasonings.

Remove from the heat. Stir in the remaining 1 tablespoon each oil and parsley. Spoon the risotto into warmed soup bowls and serve immediately.