"Let her go," said Sir Percival, "for a maiden, wheresoever she cometh, is free." "Whatever maiden passeth here," replied the knight, "must give a dishful of her blood from her right arm." "It is a foul and shameful custom," cried Sir Galahad and both his fellows, "and sooner will we die than let this maiden yield thereto." "Then shall ye die," replied the knight, and as he spake there came out from a gate hard by, ten or twelve more, and encountered with them, running upon them vehemently with a great cry. But the three knights withstood them, and set their hands to their swords, and beat them down and slew them. At that came forth a company of threescore knights, all armed. "Fair lords," said Sir Galahad, "have mercy on yourselves and keep from us." "Nay, fair lords," they answered, "rather be advised by us, and yield ye to our custom." "It is an idle word," said Galahad, "in vain ye speak it." "Well," said they, "will ye die?" "We be not come thereto as yet," replied Sir Galahad. Then did they fall upon each other, and Sir Galahad drew forth his sword, and smote on the right hand and on the left, and slew so mightily that all who saw him thought he was a monster and no earthly man. And both his comrades helped him well, and so they held the field against that multitude till it was night. Then came a good knight forward from the enemy and said, "Fair knights, abide with us to-night and be right welcome; by the faith of our bodies as we are true knights, to-morrow ye shall rise unharmed, and meanwhile maybe ye will, of your own accord, accept the custom of the castle when ye know it better." So they entered and alighted and made great cheer. Anon, they asked them whence that custom came. "The lady of this castle is a leper," said they, "and can be no way cured save by the blood of a pure virgin and a king's daughter; therefore to save her life are we her servants bound to stay every maid that passeth by, and try if her blood may not cure our mistress." Then said the damsel, "Take ye of my blood as much as ye will, if it may avail your lady." And though the three knights urged her not to put her life in that great peril, she replied, "If I die to heal another's body, I shall get health to my soul," and would not be persuaded to refuse. So on the morrow she was brought to the sick lady, and her arm was bared, and a vein thereof was opened, and the dish filled with her blood. Then the sick lady was anointed therewith, and anon she was whole of her malady. With that Sir Percival's sister lifted up her hand and blessed her, saying, "Madam, I am come to my death to make you whole; for God's love pray for me"; and thus saying she fell down in a swoon.