The Elder of Arcaneness is needed for Ascension, and provides numerous other options. He is used to complete the daily quest Sky Lotus. You can trade him your Affinity Beads for affinity and can purchase various items with Arcane Bullion and Arcane Coins.
Among other items, he sells upgradable rings, Esper Tomes and Accessories, Faction Charms, Clan Upgrade items, and trinket recipes.
Location: Jadeon (4, -433) Note: This NPC is located at the top of the tower at his location.
NPC Text Edit
There's never an end to my work. Maybe you can lend a hand? But I don't think you have enough skill to tackle tasks such as I have.