Place lima beans and 1 slice bacon in a medium saucepan; cover with water. Bring to a boil over medium-high heat, then turn the heat to medium-low and simmer until the beans are just tender, 8 to 10 minutes. Drain the beans and set aside. Discard the bacon.
Meanwhile, add the remaining bacon to a large cast-iron skillet over medium-high heat. Cook, turning occasionally, until crispy, about 8 minutes. Remove the bacon to a plate or bowl and set aside.
Melt the butter in the skillet with the bacon fat. Add the onion and cook until softened, 2 to 3 minutes. Add the corn and the garlic and season with salt and pepper (about 1/2 teaspoon of each). Cook until the corn is just barely cooked, 3 to 4 minutes. Stir in the okra and cook until tender, another couple of minutes. Add the tomatoes and drained beans and continue to cook until the corn is tender, 2 to 3 minutes. Add the lemon juice, then taste for seasoning.
Chop the reserved bacon and sprinkle on top along with the chopped parsley. Serve warm or at room temperature.