Maester Luwin from A Clash of Kings is a kindly old man who has served Winterfell for many generations. When Ramsey storms Winterfell he puts a sword into Luwin and leaves him for dead. Bran, Osha, Rickon, Meera and Jojen find him by the Godswood. He urges them to flee and for the boys to separate for their own good. He begs Osha to kill him quickly as he knows the stomach wound will be a long, tortuous and lingering death. Osha presumably does so when the boys are further up the trail.
