Pledge of Friendship

A Pledge of Friendship is a container item gained during the Love is in the Air event.

Source
When you give a Love Token to a guard NPC from one of the major cities of your faction (excluding Exodar and Silvermoon) while you have the Adored debuff, you gain a Pledge of Friendship. A non-guard NPC will give a Gift of Friendship which is similar, but has a different name, item id, and contents. You can keep gaining Gifts of Friendship and Pledges of Friendship while you have the Adored debuff.

You gain the Adored debuff by giving a Love Token to a guard NPC exchange for a Pledge of Adoration and the Adored debuff or to a non-guard NPC exchange for a Gift of Adoration and the Adored debuff.

You cannot get the pledges nor gifts of the other faction, since you cannot talk to the NPCs.

Items
There are 6 separate Pledge of Friendship items, depending on the source city:
 * Alliance
 * Pledge of Friendship: Darnassus contains either Sentinel's Card or Pledge of Loyalty: Darnassus
 * Pledge of Friendship: Ironforge contains either Ironforge Guard's Card or Pledge of Loyalty: Ironforge
 * Pledge of Friendship: Stormwind contains either Stormwind Guard's Card or Pledge of Loyalty: Stormwind
 * Horde
 * Pledge of Friendship: Orgrimmar contains either Grunt's Card or Pledge of Loyalty: Orgrimmar
 * Pledge of Friendship: Thunder Bluff contains either Bluffwatcher's Card or Pledge of Loyalty: Thunder Bluff
 * Pledge of Friendship: Undercity contains either Guardian's Moldy Card or Pledge of Loyalty: Undercity

Tips
The content items of the Gifts and Pledges of Friendship are not directly usable by your character. The goal with these items is to build sets that can be turned in for buffs and items. You will need five of the Gift of Friendship items and five of each of the two Pledge of Friendship items, all from one city, to complete a turn-in. The stacks of five are each combined into an item collection, and then the three collections are combined into a City Gift Collection which can be turned in.