Titus Groan grandiose wit which he uses on the castle's less intelligent inhabitants. Despite his acid tongue, he is an extremely kind and caring man who also is greatly fond of Fuchsia and Titus. (In a few places in the text, Dr. Prunesquallor is given the first name of Bernard, but this was an error by Peake.) He lives with his sister Irma Prunesquallor. Though she is anything but pretty, she is considerably vain. She desperately desires to be admired and loved by men. In this position, Steerpike is able to come into even closer contact with members of the Groan family,
Titus Groan to tell the twins that they were invited as well, strengthening their feeling of bitterness towards Sepulchrave and Gertrude). He intends to lock the doors to prevent an escape, and then come through the window and save everyone inside from the fire, appearing as a hero and possibly strengthening his position and granting him more power in the castle. Everything goes according to plan: the entire Groan family (including the Earl and his heir) and most of the retainers are saved. Sourdust, the old Master of Ceremonies, dies of smoke asphyxiation and all the books in the library are destroyed