In Chapter 4, Laura uses a simile to describe the effect of Carmilla's loving words and "trembling embrace":
My energies seemed to fail me. Her murmured words sounded like a lullaby in my ear, and soothed my resistance into a trance, from which I only seemed to recover myself when she withdrew her arms.
Laura compares Carmilla's words to a lullaby. This unusual comparison suggests that her words have a soothing quality that resembles the comforting sound of a lullaby sung to a child. Lullabies are, of course, known for their gentle, rhythmic and tranquil nature and are sung specifically to lull a person into a state of relaxation or sleep. Le Fanu's simile thus conveys how Carmilla's words have a profound impact on Laura: they have a hypnotic quality and lull her into a trance-like state. This description implies Carmilla's speech has a mesmerizing effect and that she exerts a subtle control over Laura's emotions and will.
The simile also evokes the gentle, melodious nature of Carmilla's voice to the reader, creating a sense of tranquility and comfort. All in all, Le Fanu's use of simile here emphasizes the power of Carmilla's speech in its ability to influence Laura while importantly suggesting a subtle manipulation or even enchantment on the part of Carmilla.
In Carmilla, the titular character is evasive despite Laura's efforts to find out about her past. In Chapter 6, Carmilla uses a simile to compare the effort of remembering her first ball to divers as they navigate through water:
I remember everything about it—with an effort. I see it all, as divers see what is going on above them, through a medium, dense, rippling, but transparent. There occurred that night what has confused the picture, and made its colours faint.
By likening the act of remembering to how divers perceive things above them through water, Carmilla implies that her effort to recall memories is difficult or distorted. This vivid and unlikely comparison suggests that her recollection is hazy and difficult to grasp, adding to the sense of mystery around he.
Carmilla also uses a metaphor to evoke her sense of memory. The phrase "what has confused the picture, and made its colours faint" likens memories to a picture that has been obscured or transformed its clarity, causing the colors and details to become faint or less vivid. Le Fanu uses both simile and metaphor here to convey Carmilla's supposed fragmented experience of memory. Le Fanu also uses this simile to underscore Carmilla's elusive nature; the obscurity around her background hints that her identity and past are not what they seem.
