How to Make It
Fill a large saucepan with 1 inch of water and fit with a steamer basket. Bring to a simmer. Place the lobster tails in the steamer basket, cover, and steam until opaque throughout, 8 to 10 minutes. Remove the tails. Using kitchen shears, cut straight down the central membrane (the thin, paler pink portion on the inside of the tail) and pull apart to break the tail in half. Remove the meat from the shell immediately (to stop the cooking) and coarsely chop. Let cool.
Meanwhile, melt 1 tablespoon of the butter in a large skillet over medium heat. Add the corn and cook, tossing, until tender, 2 to 4 minutes. Transfer to a large bowl and let cool; reserve the skillet. Add the lobster, celery, mayonnaise, lemon juice, and ¼ teaspoon each salt and pepper to the bowl and toss to combine.
Brush the insides of the buns with the remaining 2 tablespoons of butter. Brown the buns, buttered-side down, in the reserved skillet over medium heat until golden, 5 to 7 minutes.
Divide the lobster salad between the buns.