As I thought, Meiling-san is related to the Honored Sage... She is probably related to the barrier too.

Beyond the barrier is the underground...?

Then...

What should I do?

...Just let it go.

If enough time has passed, or perhaps...

I knew it.

If I defeat you,

will that barrier come apart?

As I have never been defeated, I cannot say I know.

Perhaps...

By "those girls"... could she mean...