Pacts with the Scathesidhe

Not all malign cults are those of demons, devils, and dark gods. The Lords and Ladies of the Shadow Kingdoms are also fond of pacts and gifts with foolish men and women. Sometimes the shadow fey take children and leave changelings behind to lead stolen lives. More often the scáthesidhe take grown men or women as lovers, and many of those do not return.
Worst of all, these humans often see the truth of the fey realms, which are so beautiful and desirable they make strong men weep and beg to return. By keeping paradise just out of reach, the fey gain devoted followers. Kobolds and dwarves seem remarkably resistant to fey blandishments. Gnomes are, if anything, fey lackeys and thralls, serving the Shadow Court as its couriers, toadies, and (sometimes) arcane enforcers.