Sanae Okonogi, or Megabaa, whose nickname stems from the Japanese words for eyeglasses (メガネ megane?) and grandma (ばあちゃん baachan?), is the owner of the Cyber Candy Shop Megasi-ya. Megasi-ya also sells software and metatags. Megabaa is the primary craftsman of metatags in Daikoku, and is an expert software programmer. She is also Yasako's grandmother, and the head of the Coil Dennō Detective Agency. Her cunning frugality terrifies Yasako among other characters. Her deceased husband was a researcher in the early medical application of dennō technology. His secret legacy is slowly unveiled throughout the series.

Her seiyu in the Japanese dub is Reiko Suzuki.