Kill Spiders, Get Delicate Silk

  is a one time Side Quest.

Journal Entry
''Those two fans of Port Harmony's fake Avatar might be crazy. They apparently want me to go to the nearby beach and kill reef spiders until I get "delicate spider silk" ...because they're going to use it to make a leash and harness for the orange butterfly I caught for them earlier! This time, Winifred said she'd pay me, so maybe there's some sense still left in them.''