I think I found it.

香塗流 塔尓莫依 川隈乃 屎鮒喫有 痛女奴

香塗れる塔にな寄りそ川隈の屎鮒食めるいたき女奴

kau nureru tau ni na yori so kahakuma no kusohuna hameru itaki meyatuko

Don't come near the incense-fragrant tower, you horrible, river-toilet shit-carp-eating bitch.

This was improvised by one Naga no Okimaro, the challenge being that his poem had to include the words "incense", "tower", "toilet", "shit", "carp", and "slave" "servant, inferior". "Toilet" was actually supposed to be 厠 (/kahaya/) but he used 川隈 (/kahakuma/, "river-nook") instead, because it was understood to mean more or less the same thing. Shit-carp (屎鮒) thrive there, natch. "Servant/inferior", meanwhile, is within the word meyakko ("woman-slave" or "female servant [derog.]"), which I have here translated as "bitch" for poetic reasons.

More information on Okimaro can be found on the internet.