Moth asks the Dragonborn to obtain Daedra heart for him. These can be obtained from the Daedra at the Shrine of Mehrunes Dagon, bought from Enthir at the College of Winterhold or bought from Babette. For all locations to obtain a heart, see here. After the quest, Moth gro-Bagol will reward the Dragonborn, and will also be a candidate for marriage.
|Coated in Blood – FreeformMarkarthN|