One sect of dark elves worships Loltharanea Daemonis (Spiders, Traps, Fate).
Nhakhramat (Serpents, Magic, Knowledge) is another favorite of the dark elves.
Most dark elven clans follow a specific patron demon, many of these demons are lower to mid level.
Graz’zt and Fraz Urblu are the only major named demons known to be worshipped by druasian clans.
Some ancient druas clans follow Tiamat, in her semi-demonic aspect as the mother of monsters.
Druas gain the Blasphemous Covenant racial trait in addition to normal drow racial abilities (not in place of).
Blasphemous Covenant: Since their twisted beginnings, the druas have consorted with demons. Some druas have strong ties with these creatures and may call upon ancient and obscene associations to sway demonic cooperation. Druas with this racial trait gain advantage 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 druas to summon a demon is reduced by 20%.