So this room was...

But

Maybe locking her in was a mistake

Have you come to catch me?

But nobody can catch me

For example you could threaten me with a silver knife

Or you could try to pierce my heart with a wooden stake

Flan, does she think I'm a vampire hunter

Fine, come at me

... It seems it's a dead end, I'll have to bring you back home, little sister

The only dead end here is your life