I’ve had a version of this in my head for a while; I cannot for the life of me remember if I’ve ever written it out before.
Stats: ST +1 , DX +1 , IQ +1 , HT +1 , HP +1 , FP +1 , Will -4 [-20]
Advantages: Appearance (Handsome/Beautiful) , Longevity , Rapid Healing 
Disadvantages: Charitable [-15], Easy to Read [-10], Enemy [varies*] [-10], Magical Susceptibility 5 [-15], Unnatural Features 5 [particolored hair, faintly glowing skin] [-5]
Racial Quirk: counts as Human for the purposes of spellcasting [-1]
*Evil magic-users or cultists will invariably show enough of a disproportionate interest in Servitors to justify at least -10 points. Depending on the culture, it may be even more — or replaced with Social Stigma [Valuable Property].
Servitors are humanoids — virtually human-like, in fact, although they cannot interbreed with human beings. Their major physiological differences lie in the hair (naturally particolored) and skin (which glows very slightly blue in dark conditions). Physically, they give the impression of being bright-eyed and graceful sophonts, pleasing in both face and form.
Mentally and genetically, however… well, the truth of the matter is that Servitors were bred for the use of necromancy, and general black magic. Their ability to resist spells, ritual casting, enchantments, and even normal blandishments has been cruelly stunted, which means that Servitors are particularly susceptible to having their lifeforce and physical attributes ripped away with foul magics. Surprisingly, though, Servitors were not bred to be an actual “slave race:” apparently that was considered to be aesthetically displeasing. So instead Servitors were bred to be unnaturally solicitous of others and to be rotten liars, which is arguably even nastier.
All enlightened realms — and a few of the less toxic authoritarian ones — absolutely ban the ownership of Servitors, whether or not slavery is normally allowed locally. It is widely (and usually accurately) assumed that any wizard that owns a Servitor will be performing dark magics on him or her in the very near future, so unless those spells are legal for use on slaves anyway the authorities might as well save valuable time and arrest the slave-owning wizard in question. Servitors themselves are treated with a combination of pity and wariness: nobody decent likes to think too poorly about a sentient species that was bred to go under the knife, but it remains true that a Servitor is horrifyingly easy to take magical control of. And most people who know what Servitors are are going to be at least a little worried about it.
This race can actually make for a decent enough player-character race, although the combination of low Will and vulnerability to magic is deliberately designed to be nasty. GMs with players who wish to buy off Weak Will may want to consider letting the player trade it in for a higher level in Enemy. Magical Susceptibility should still always be retained, however: it’s more or less integral to the concept.
The material presented here is my original creation, intended for use with the In Nomine and GURPS systems from Steve Jackson Games. This material is not official and is not endorsed by Steve Jackson Games.
In Nomine and GURPS are registered trademarks of Steve Jackson Games, and the art here is copyrighted by Steve Jackson Games. All rights are reserved by SJ Games. This material is used here in accordance with the SJ Games online policy.