The material below is Open Game Content from a 3PP Source
Blasphemous Covenant: Since their twisted beginnings, the drow have consorted with demons. Some drow have strong ties with these creatures and may call upon ancient and obscene associations to sway demonic cooperation. Drow with this racial trait gain a +2 bonus on Diplomacy checks made against unbound creatures with the demon subtype. Furthermore, demons conjured with any summon spell gain +2 hit points per Hit Die. Lastly, the cost of bribes or offerings for any planar ally spell cast by these drow to summon a demon is reduced by 20%. This racial trait replaces keen senses and poison use.