Well, the succubus is the female version of the incubus, and as such her motives are similar. Rather than pin down her victim, she begs to be taken, she woos victims with her feminine qualities, and when that does not work, with persistence. Her role is as pure distraction- you see, Succubi do not directly consume their victims- their insect-like mouthparts do not allow for ‘biting’ or the ingestion of flesh directly.
Each succubi differs from dream to dream, based on the tastes of the men in question. Smaller breasts, a different face, a smaller child like frame- each dream defines the appearance of the succubi.
A man finding the allure of the succubus irresistable will have his lifeforce drained as he gets penetrates her. This is the equivalent of a feast to a succubi. However, there is a catch- resistance. This is dealt with tactically- A single or group of succubi may tempt an unwilling victim over the edge of a cliff so that she may lap up his blood and squishy parts as they rot to a more easily digestible solution.
Those who persist in their rejection of the succubi are ‘kept busy’ until help arrives…
While the incubus and succubus do not get along ‘socially’, certain succubi discovered long ago that what the incubus lacks in charm can more than be made up for by the more alluring succubus. The incubus gets a meal, and in payment the succubus gets a small amount of freshly regurgitated meat- far more palatable than the alternative.
If you see a succubus it is advised that you stay on guard, and if possible flee the area as quickly as possible. She may not be single…
In the context of project zodiac, the succubus does not represent the desires of the protagonist, instead, her appearance is that of what she hopes will work. This is due to two factors- the protagonists attitude to women and his obscure sexuality.
The official canon is that the protagonist is so taken in by his work that he has no time for women-he sees them as a distraction and as such the succubi become one in his dream. However, as this whole jazz is for a game concept, the extent of the characters lust is down to the gameplay style of the player. Those who are drawn to the succubi through their own lust for the women with the boobies will have a more sexualised experience than those who avoid the succubi or focus on killing them.
This is in contrast to the incubus- who is a single, unstoppable creature in control at all times, a solid representation of certain parts of the characters life. If a player gets too chummy with the succubi, an incubus will show up. If a player avoids the succubi at all times, the incubus will still show up. If the player is standing around dawdling or camping out sniping, the incubus will show up. He’s just that kind of guy.