Bring a large pot of salted water to a boil.
Add the fettuccine and cook for 8-10 minutes until it's just shy of al dente.
Drain, reserving 1 cup of pasta water.
Heat olive oil in a large skillet over medium-high heat.
Add the cherry tomatoes and cook until they start to blister.
Add the crab meat to the skillet.
Stir gently for about 2 minutes until it's warmed through.
Toss the cooked pasta into the skillet with the tomato and crab mixture.
Add the butter, Parmesan cheese, and reserved pasta water.
Stir until the butter melts and forms a silky sauce.
Season with salt and pepper to taste.
Stir everything gently and serve hot.