It's almost Christmas in Akihabara.  At Lenessia's mansion, Marie and Henriette are all visiting.  Lenessia is smiling, but she can't open herself up to the adventurers because of how different they are.  Akatsuki, who has been tasked with guarding the princess, is the only one who isn't having fun.  She thinks of Shiroe and worries about her own powerlessness.  Then, in Akihabara in December, a shocking event occurs.
If you're happy, you say you're happy.
Ist man fröhlich,
verhält man sich fröhlich.
Si estás feliz, lo dices también.
« Tu es heureuse ? Alors souris. »
Se sei felici, devi dire di essere felice.
Se está feliz, também fala que está feliz.
Когда радостно — радуются.