Summoner Calwen

Summoner Calwen is a warlock trainer located in the Sunreaver's Sanctuary in the mage city of Dalaran.

Quotes
I can sense your desire for power,.
 * Warlock gossip

I apologize,. I mistook you for someone with a spine. Begone; our secrets are not for untrained ears.
 * Non-warlock gossip

Speculation
Given the fact that the NPC reuses the model of Delano Morisett, it is possible that Blizzard originally planned to use that character instead of race-changing a blood elf into a Forsaken with no explanation.