Bat demons are notoriously known for their intriguing speech patterns. Paralleling their counterparts in the mortals' natural world, Bat demons utilize echolocation as a means of finding things more clearly in daylight. While the idiomatic phrase 'blind as a bat' has become popular among both the mortal and immortal realms, bats are not actually blind, but rather are nocturnal and thus use echolocation to find food during the nighttime hours when things are harder to see. Similarly, bat demons are not blind, but have a difficult time seeing in daylight. This difficulty is created by a sensitivity to light that causes their brains to slightly misinterpret the sensory information from the optic nerve which in turn results in blurry images with, at times, misrepresented distances. The remedy to this minor affliction is the use of echolocation for similar purposes to those of the mortal counterparts.

Bat demons can use a limited form of penetrating sound waves in order to receive correct sensory information through the auditory nerve that can overrule the misinterpreted information from the optic nerve. This technique, however, is far more advanced and accurate than the typical 'echolocation' of mortal bats. The cause of this is the fact that the extra sensory information is used only to add corrections to the interpreted visual information rather than entering the brain in a seperate form.

The penetration strength of the sound waves bat demons use is higher than that of mortal bats as well. Bat demons have unique vocal cords that allow their speech to take on a stronger level of compressions. While demons have certain adjustments to their nervous systems that help their sensory organs to adapt and adjust sounds to a general level, humans can easily pick up on the difference. Interviews with several such humans has revealed the sound seems to reverberate around the inside of the cranium which can leave the human disoriented and surprised until they become more used to the effects and their brains learn to treat them as background noise. Selective attention then sorts the information out as unecessary, but it takes a good amount of time to reach this point, leaving humans vulnerable against the extraordinarily unique speech of these demons.