Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Honorbound Retainer's Sash Compares
Who It Suits
Cloth is the armor type Mage, Priest and Warlock wear. With Intellect, Honorbound Retainer's Sash suits Discipline, Holy and Shadow Priest; Arcane, Fire and Frost Mage; Affliction, Demonology and Destruction Warlock.
Transmog Sets
Honorbound Retainer's Sash is part of the transmog set Threads of Awakening (Priest, Mage and Warlock only). The other 16 pieces:
Blizzard numbers items as they are created, so the named items next to ID 221121 (221116 to 221126) were usually added in the same batch as Honorbound Retainer's Sash: the same quest line, zone, vendor or reward set.