"Oh… I get it," Luna exclaimed. "Since the room changes depending on what you need, it will probably change every time you use it. The room comes and goes, thus 'Comes and Goes' room," she stated.
Dobby cocked his head to the side and thought about what Luna had just said. "Hummm… Dobby never thought of it that way, but that works too," he said with a shrug of his tiny shoulders.
Hermione rubbed her forehead with her hand and muttered, "I know I'm going to regret asking this, but why do you call it the 'Comes and Goes' room, Dobby?"
Dobby pointed down the hall to a similar tapestry hung at waist level. "The castle also has a Comes and Goes room for House Elves. It's being a very popular place for House Elves to go and practice making House Elf babies. It's being so popular of a room that there is a waiting list the House Elves have to be getting on to use the room. Almost all the House Elves is being very considerate of others and want everyone to get their turn. So…" he explained.
Hermione pinched the bridge of her nose, her earlier premonition being correct. "No… don't say it Dobby," she pleaded.
Since she was not his mistress, yet, Dobby could ignore her order. "... after boths of the House elves comes, theys goes so the next House Elves can have their fun," he finished.