Heat oil in a large skillet over medium-high heat. Add ginger and paprika and cook, stirring constantly until fragrant, about 20 seconds. Add walnuts; saute until lightly browned.
Add shrimp; cook and stir until pink and opaque, about 2 minutes per side. Stir in turnips, vinegar, sake or rice wine, salt, and pepper; cook and stir until heated through, about 2 minutes. Stir in parsley. Serve warm.