Ah! My Goddess S01 E22 Ah! A Devil's Whisper, Along With a Pot?

"Seinen"

Mara retrieves a demonic urn from a cave. Urd's goddess license had been suspended, which motivates her to look for a regular job. But when things go bad there she accepts her demonic heritage and transforms into the Lord of Terror! Big Trouble for Keiichi and the gals!