Location: Dalimil Inn
Petitioner: L'ubor
Unlocked: Complete Through the Maelstrom
Reward: 120 Magicked Ash, 1 Meteorite, 30 Renown
In order to unlock this side quest you need to complete Through the Maelstrom, a main story quest that will take you out to sea. Return to the Hideaway and Lines in the Sand will be waiting, elsewhere in the world.
Travel to the Dalimil Inn and speak to L'ubor, who is standing out front of his shop, across from the Obelisk. Apparently L'ubor is going to be the mayor of Dalimil, which is good news. The bad news is that the region's bandits have decided to threaten Dalimil as a united force, and L'ubor wants Clive to scare off any unrecruited ne'er-do-wells before they're pulled into the conflict.
Accept the quest and L'ubor will send you to speak with Viktor, another familiar face, near the Desert Gate in the northeast. He wants Clive to deal with a camp of bandits to the northeast, in the Southern Velkroy Desert. Trek through the sand, following the river to the north of the town, and you'll find the camp with little trouble.
The bandits' numbers include several League Footpads and two Unleashed Hounds. Defeat the first squad and more League Footpads will show up, along with two League Cunning-men. The latter enemies are magic users that can cast Cure, and should be eliminated first. Take out both squads of enemies to receive Steelsilk, Bloody Hides, and Magicked Ash.
Defeating the bandits will bring Viktor over to meet Clive, and he'll have a revelation that takes the pair back to Dalimil. Enter the Final Sting (the tavern) and speak to Konrad, then talk to L'ubor again to end the quest. Poor guy.