What is Tentacle?

Tentacle hentai is one of the oldest and most iconic genres, featuring tentacled creatures in sexual scenarios. The genre traces back to Hokusai's 1814 woodblock print 'The Dream of the Fisherman's Wife.' Modern tentacle hentai was popularized by the 1986 OVA Urotsukidoji. While sometimes used as shorthand for all hentai in mainstream media, tentacle content is actually a specific niche within the broader hentai ecosystem.