Douglas tapped rhythmically on the storeroom door, then stepped back as though someone were behind it. The door suddenly opened on its own.
Standing behind him, Harry found it very strange. Not a trace of light passed through the open door, and the interior remained pitch-black at a glance. In particular, the moment his maternal cousin entered, he seemed to be swallowed by the darkness, disappearing completely from Harry's sight.
He was all too familiar with the cupboard under the stairs. It definitely had not been like this.
Sirius shrugged and explained to Lupin and Harry, "It's a little magical mechanism, like the entrances to the various Common Rooms at Hogwarts. He once wanted to make the password for the Kitchen door work like the entrance to the Hogwarts Kitchens, too, but later decided it was too much trouble and dropped it."
Lupin said thoughtfully, "I've heard that the entrance to the Hufflepuff Common Room requires you to tap out the correct rhythm of 'Helga Hufflepuff.' His design must be something like that."
Dobby said excitedly, "Mr. Lupin guessed correctly, but this door isn't that simple. The boss's idea is great, and his design is even better. He even let Dobby help design this door, but that's a secret for now. Dobby is very sorry he can't say."
Harry looked around in amazement. To him, this was what a wizard's home ought to be like, with wondrous magic everywhere.
Ordinary wizarding families probably would not put things like this in their homes, though. Even the Weasley family's Burrow did not have such a complicated way of opening doors. He wondered whether the house Sirius had mentioned was just as magical.
While Harry was still lost in thought, Sirius had already stepped into the storeroom, leaving behind only his voice. "Keep