The term 'Grail Seeker' refers to three characters from Arthurian legend: Galahad, Parsifal, and Percival. Galahad is the son of Lancelot and a knight of the Round Table who is known for his purity and strength. Parsifal is a knight who is the protagonist of the story of the Holy Grail and is known for his innocence and naivety. Percival is another knight of the Round Table who is known for his quest to find the Holy Grail. All three of these characters are associated with the search for the Holy Grail.