Unlike the original Star Ocean: The Second Story, Star Ocean The Second Story R helpfully displays side quests on the map when they pop up, as 'Sub Events'. This may clue you in to the presence of an event in Salva, once you've completed the Lacuer Armory Contest. You should promptly check this out.
Fast Travel to Salva and check just north of the Save Point, in the south of town. There's a scholar here by the name of Ruddle the Traveler, and he's... lost. Very lost. Ruddle is trying to get to Harley, and he needs a bit of help with the directions. Point him out of Salva appropriately by telling Ruddle to go north.
Ruddle will leave Salva. If you check the map again you'll see another Sub Event over in Marze. Fast Travel there and check the Item Shop. You'll find Ruddle inside, and he's freaking out, because, you know, this still isn't Harley. Tell him that Harley is further east of here to send Ruddle on his way a second time.
Check the map again. The next Sub Event won't be in Harley, but rather Hilton. Looks like Ruddle overshot a bit. Fast Travel to Hilton and check out front of the food stall that's parked beside the Inn. Ruddle still can't seem to find his way. Tell him to travel by boat again and he'll run off to the port.
This will do the trick, although another Sub Event won't appear on the map. Head to Harley and check to the left of the front desk. Ruddle is waiting, and as a thank you for getting him here he'll give you the Scumbag Slayer. The Scumbag Slayer is an odd, low-power little weapon that can instantly kill any enemy with the word 'Scum' in its name. Most of the enemies tend to be weak, so the Scumbag Slayer doesn't seem very helpful...
... but there's a major caveat. Much later in Star Ocean The Second Story R there's a post-game dungeon that you can tackle, and on one of its floors you'll find nigh-invincible enemies with 'Scum' in their names. The only way you'll get through these battles is to have a Scumbag Slayer equipped on one of your characters. Don't sell it, don't try to Customize it, don't throw it away, just keep the Scumbag Slayer for the post-game. Enjoy!