Krilner, from Ultima Underworld II
Krilner is a real weakling trapped inside the prison that are the Pits of Carnage.
He was the first person the Avatar met in Ultima Underworld II and acted like a real coward. His pathetic attempt to battle the Avatar ended when he surrendered after getting a scratch. Then he claimed to be the Avatar's slave, and the Avatar reluctantly agreed, since otherwise the desperate Krilner would attack. After that, Krilner told the Avatar about the Pits, and how the other warriors actually ignored him since he was such a weakling, calling him "Krilner the Coward". He turned out to be a spring of information however, being all too eager to please the Avatar, telling the hero everything what desired about the Pits.
Later, when the Avatar needed to defeat Dorstag, Krilner revealed to him that defeating Zaria would likely impress Dorstag into a duel, after Dorstag had denied the first challenge. After Dorstag's defeat, Krilner almost literally kissed the Avatar's feet in admiration.