Few conventions are "purely" anything, but the following conventions are associated with Gothic literature: intimations or the presence of death, a setting at a castle or a lonely, isolated spot, a feeling of horror, dread or gloom, a woman or women (or man) in distress, often threatened by a tyrannical creature, the presence of monsters or vampires, and a mystery.
Dracula focuses on a vampire and the need to destroy the threat the creature poses as he heads back out into the world after a long hiatus in Transylvania. The novel opens at his gloomy, frightening castle in an isolated, foggy setting. From the start, Dracula himself, who never comes out by day, never eats and whose face cannot be seen in a mirror, is a frightening character who increasingly fills our narrator, Jonathan Harker, with a sense of horror. Dracula is able to possess other animals that traditionally fill humans with dread, such as wolves or rats. He will threaten to turn the women close to our narrator, such as his fiancee Mina and her friend Lucy, into vampires. He presents a mystery: who is he, how can such a creature exist, how does he function, and how can he be stopped?