The Tickler

The Tickler is an antagonist in A Song of Ice and Fire and Game of Thrones. He is a sadistic soldier and tortue technician who serves with "the Mountain's Men" under Gregor Clegane.

The Tickler is of medium height and build, with a face so ordinary it's difficult to establish his age. He asks the same questions to every victim, such as "was there gold hidden in the villages", "where is Lord Beric" and "which of the village folk aided him".

The Books
The Tickler first appears in A Clash of Kings, where he and his companions capture Arya Stark, Gendry and Hot Pie near the Gods Eye. He tortures several peasants to gain information about the Brotherhood without Banners, causing him to be added to Arya's kill list. He later leaves Harrenhal to be part of the Mountain's vanguard. After the Mountain recaptures Harrenhal, the Tickler and Polliver take a squire from Sarsfield to the Crossroads Inn to lose his virginity. They encounter Arya and the Hound, who claims that the men are trying to torture the innkeeper to find gold. A fight ensues, and the Tickler is stabbed to death by Arya.

The show
The Tickler serves as a soldier under the Mountain, who every day selects a man to be questioned while tortured by him. When Arya, Gendry and Hot Pie arrive in Harrenhal, they are lined up for choosing. A man next to Hot Pie claims that he stares at the Mountain every day which is why he never gets chosen. However, due to Hot Pie's mimicking, Gregor picks the man as a taunt.

The Tickler straps a bucket of rats to the man's chest. There, his assistant Weasel lights a fire on the base of the bucket, forcing the rats to crawl into the man, while the Tickler asks his usual questions and eats a pear nonchalantly. Arya then gives his nickname to Jaqen H'ghar as a debt to repay Arya for rescuing him from the fire. The Tickler is pushed off a balcony by Jaqen and breaks his neck.

Trivia

 * The Tickler's death in the show was from Chiswyck, another one of Mountain's Men, in the books. His book manner of death was given to Meryn Trant.