Daeo Alar Gullamir 

Background

Daeo was cursed in battle with the Illidari

he is forced now to roam the two worlds as a Incubus he trys his best to hide it but its just not enough sometimes most of the time when he is caught the guard or spy is usually swimming in a pool of there own blood within the hour..These beings are attracted by the use of magic as well as by sexual desire and frustration. Once they decide they like someone, that person will generally receive multiple visitations over the course of his or her life. Some people regard the exchange of a little energy for the sexual pleasures offered by these beings to be well worth it, and will seek to encourage visitations by them.

he acts very strong and happy and is clearly a very happy person..

How he feeds and mates:

He drains energy from his victim by causing or taking advantage of sexual arousal or frustration. In this time, monks, nuns, and other celibates were particularly unfond of these beings, as they manifested to them with some frequency, due to the sexual frustration which is often an innate part of celibacy.
a Incubus's experiences are usually pleasurable for the victim, and will only cause any problem if they are already extremely ill or weak, although they may not. Some vampiric magicians dislike these beings as they hate being drained of vital energy.
It seems to only be rarely in modern times that an incubus experience will not be regarded as pleasurable. Generally, these will be situations in which the entity explores the hidden sexuality of it's victim (for example, appearing as a male to a homophobe). This exploration of hidden and forbidden sexuality is part of what made the lights church revile them to such a great extent and regard having sex with them as so sinful.
Thomas Aquinas, darling of the lights Church and   founder of "scholasticism," believed that devils, in the form of incubi, performed fellatio on sleeping mortals. Then, as incubi, they used the seed so obtained to impregnate virtuous unmarried women in their sleep, thus producing half human/half demonic monsters. In fact, this was a convenient excuse for unmarried women who became pregnant, more often than not.