Ms. Sara Bellum’s Address
This easter egg is seen in Season 2, Episode 13a titled "Something's a Ms."
During the Season 2 episode, “Something’s a Ms.” while attempting to save Ms. Bellum after she is held for ransom, the Powerpuff Girls fly to her house where we get to see Ms. Bellums address on her mailbox.
Her address is 69 Yodelinda Valley Ln.
For those who don’t know, Yodel in the valley is a reference to oral sex on a female and the 69 bit… Well, you can probably figure that one out.