"Petyr" - the image of a short, skinny boy with smart eyes and a secret on the lips popped into her mind, followed right away by bitter thoughts. She still could remember their argument like it had happened yesterday. Her trying to stop him, telling him how insane this whole thing was. Petyr couldn't beat Brandon, a man grown, in a fight. He would get himself killed, and for nothing. But Littlefinger blinked, his green eyes full of dreams, and gave a small smile. Suddenly he bent his knee, asking for her favour. If he had it, he would win, the boy promised to Cat. "He really believed in that." She stared at him - Catelyn couldn't give her favour to him; she was pledged to Brandon Stark. It was a political union to bring House Tully to Robert's Rebellion, not some lovely tale, and she had to do her duty.
When the opponents met in Riverrun's courtyard both of them were wearing light armour. Petyr hadn't another one and Brandon had to be as fast as his opponent. The only way Littlefinger could possibly defeat him was by slowing him down. Catelyn could still hear Petyr's screams, cutting through the courtyard right into her soul. He was her best friend though his feeling were deeper than hers. Petyr was the one she told all of her secrets, wishes and fears. The duel had barely started and Petyr was already defeated, Brandon's sword on his neck.
When Brandon was ready to deliver the final bow, it was Catelyn's voice which yelled, "Spare him, my Lord! Please! Please, spare his life. He is just a boy. Please." She begged to her betrothed, warm tears running through her cheeks, pale from fear. Quickly, she brushed them away with the sleeves of her gown. She couldn't cry. Brandon looked at her, his grey eyes filled with a fury she had never seen in him before. Catelyn thought she knew him, and they had even shared a kiss. She couldn`t move, her body trembled beneath the gown. Lord Hoster Tully stood by her side, and she felt his disgust too. He took her arm, trying to lead her back to the seat, but Catelyn didn't move, she just stood there, like a marble statue upon a field of rage and tears. She couldn´t let Brandon kill Petyr. Catelyn wouldn´t back down. "Please, my lord, spare him. For the love you bear me, let him live", she begged one more time.
Brandon´s eyes showed no emotion, just an icy fire as he pursed his lips. And then, without a word, he turned to Littlefinger and stared at the boy laying upon the cold ground, soaked with sweat. Petyr didn't care about Brandon, nor about his own life anymore. He was looking to her. "Cat," he whispered, and now the smart eyes were just a green blur. Catelyn held her breath, but before she could let go, Brandon stuck his sword on the boy's belly, and dragged it almost up to Petyr's neck. Littlefinger screamed in agony but the shame was more painful than everything else. The crimson ran, drowning what there was left of his torn clothes and ordinary armour . Catelyn's betrothed bent near him, so close he could feel the warmth coming from his body and smell the salt of his sweat "Today you live, but if you ever cross my way, or hers, there will be no mercy.", he said in a low voice.
Brandon gave his sword, bathed in blood, to his squire, and then his eyes met Catelyn's, blue and wet with tears she wouldn't let run down her face. He came towards her with strong and self-confident steps. Brandon took Cat's hands and kissed them, tenderly. She didn't say a word. Everybody in the courtyard applauded the mighty knight, but none besides her noticed the servants taking Petyr away on a litter.