If this is:
They are designed to look like 2D illustrations even when moving in 3D. kamihikokimmd link
When the message arrived—weeks later in her sister's mailbox, tucked inside a rarely opened cookbook—the reply smelled of cinnamon and tears. They met on a bench by a river that ran the same color as nostalgia. They talked for hours, trading small, true things like currency. Kira learned that links, once mended, didn't only carry the words you intended; they carried the courage to mean them. If this is: They are designed to look
If your search for "Kamihikoki" is related to the darker, mechanical "Calne Ca" style often associated with vocaloid PVs, Deino3330's DeviantArt kamihikokimmd link