Succubus (species)

Difference between individuals
The level of the abilities of succubi entirely depends on the individual. As Michiru's Charm wasn't enough to do anything with Keima, Keima's Succubus form can subdue almost anybody - male and female included.

Succubus Queens are nightmares, they’re like living natural disasters.

Racial Abilities
As the wiki page implies succubi are a race that takes the energy of men while they are dreaming. Kosaki's abilities are listed here as well, even though it is a Ring Succubus. Their power can actually alter their clothes as well, as it was seen with their nun-clothes
 * Dream Invading
 * Dream Walking
 * Charm
 * Possessing
 * Telepathy

Notable Succubi

 * Keima - possessed by Kosaki
 * Succubus Puppy - possessed by Kosaki
 * Suilla
 * Michiru
 * Chloe