is one piece episode 12 filler?

The crew prepare for the incoming attack. As the only entrance to the village is a single sloped path at the island's south end, they stand guard at the pathway to prevent the Black Cat Pirates from entering.

They cover the slope with slippery oil to prevent them from walking up the path. Kuro, still disguised as Klahadore, returns to Kaya's mansion, where Kaya is already asleep and Merry tending to his duties.

Kuro finds a gift Kaya got for him, a pair of glasses custom-made for him so they would not slip off his nose. Kuro destroys the pair of glasses, revealing his true self to Merry.