One of the requests from the museum includes this sentence:

"The admission of 'mice' is not permitted."

If you look closely behind Doraemon while he is eating his Dorayaki...

Oh, look, there’s one here too.

It seems a few mice have managed to sneak into the museum.

If you find them, keep it a secret from Doraemon!

One of the requests from the museum includes this sentence:

"The admission of 'mice' is not permitted."

If you look closely behind Doraemon while he is eating his Dorayaki...

Oh, look, there’s one here too.

It seems a few mice have managed to sneak into the museum.

If you find them, keep it a secret from Doraemon!