Azumanga Daioh, episode 2, after Osaka's hiccups are cured?
It basically means and they all lived happily ever after. Maybe Ookami-san and her 7 comrades? It gets used a lot there because of the nature of the show. Also, the last line of hirigana in the last textbox actually says medetashi medetashi :3
Most fairy tales in Japanese start with mukashi mukashi (a long time ago) and end with medetashi medetashi (happy ending). It's in the commentary, too.
Woo!Woo!Eh? Everyone in the same room? Super!Wokyuu-chan came!?Shimakazeeee
Your voice is too loud!And so, Wokyuu-chan's fun-filled day came to a close.
All's well that ends well.Wokyuu-chaaaan!Staying over today?
You're staying over, right!?Wha? Wokyuu-chan's already asleep?