This small quest will let you raise your faction with the Yunjo Slave Resistance, the elven people native to the zones of the Gates of Discord expansion. This faction is important for getting quests to progress through the Gates of Discord zones, particularly the Breakdown in Communication quest. There is an excellent guide to this hosted on Samanna's Reference Desk, among other places.

In Riwwi there are Enslaved Yunjo are being held in the first building on the left from the Qinimi zone line. Note that there are nasty critters betwen the enslaved yunjo and the zone, as well as in the room with the enslaved yunjo themselves. Some see invis but not all. You will still need to drop invis to hand over the food and drink, however. It is reportedly possible to position yourself juuust right to be barely out of agro range of the meanies to do these turn-ins, but it will be risky.

Every twenty or thirty minutes, each enslaved yunjo will despawn and be replaced with yunjo named "thirsty yunjo", "hungry yunjo", "famished yunjo", "starving yunjo", or "emaciated yunjo". If you Hail them, they will ask for a particular food or drink. The foods or drinks they want are all made by baking or brewing some of the items available in GoD.

The foods they request are as follows:
Thirsty yunjo - any variety taelosian tea
Emaciated yunjo - any variety crab food
Famished yunjo - any variety tuna food
Hungry yunjo - any variety hynid food
Starving yunjo - any variety cragbeast food

It is unlikely that recipes using tuna or crab from zones outside GoD will work, although this has not been confirmed.

Any of the prepared foods made from the right meat should be acceptable to these yunjo, provided it has the particular meat each yunjo requests. However, there is some evidence that meats made from recipes with higher trivials will give bigger faction hits. One report says that 500-600 spiced meats and sandwiches will get you from dubious to warmly while approximately 250 steaks will get you from dubious to ally.

You need to give the yunjo eight of the food or drink they request. You then receive a small bit of experience and boost to your faction. That yunjo will then despawn and be replaced in about 30 minutes by either another thirsty/hungry/etc yunjo or by an enslaved yunjo that will not request anything.