In "The Castle of Otranto," Manfred, the lord of Otranto, has two children: his daughter Matilda, an exceptionally beautiful eighteen-year-old virgin, and his son Conrad, who is three years younger and physically unappealing. Despite Conrad's unpromising nature and illness, he is the favored child of Manfred, who shows little affection toward Matilda.

Manfred has arranged a marriage for Conrad with Isabella, the daughter of the Marquis of Vicenza. This alliance is solidified, as Isabella has been entrusted to Manfred by her guardians, and he intends to proceed with the wedding as soon as Conrad's health allows it.