There's a nice little feature on the official Twisted Wonderland website that randomly sorts you into an NRC dorm. Since this feature does not exist on the English version of the site, I'm providing a translation of the narration for boarders who don't speak Japanese. You can skip the narration if you wish.
After you enter the link I gave above or navigate to it from the "special" page (second button down), you'll be taken to a warning screen informing you that the content plays sound. You must press ON to proceed; pressing OFF takes you back to the home page.
Welcome to magic academy Night Raven College's experience entrance ceremony.
I am the headmaster Dire Crowley. Everyone, please hold up your invitation papers to the light.
After this, an invitation paper appears at the bottom of the screen; you swipe
it upward if on mobile and click
on it if on PC. Mobile devices must be oriented vertically
Are you ready? In an actual entrance ceremony, it's the Dark Mirror who chooses for you dorms that best fit your souls. Today's ceremony however is for experience purposes only, so I've made an exception: I will choose your dorms using my magic. Am I not awfully kind and generous?
By the way, as today's ceremony is different from official sorting procedure, please refrain from making complaints about dorm selections.
Let us begin. One, two, three.
On your invitation papers are now key holes connected to the gate of NRC. Now, go ahead and take the invitation paper out of the light, place the key hole over your eye and peek through the gate.
To where is your soul lead?
Here, click on the "ゲートを除く" (peek through the gate) button below the invitation paper to get your result. Unfortunately I'm not translating the dialogues provided by the characters after this screen; you can send me the final image of the result provided on the "share" screen at the end.
The first time I tried this, I got Octavinelle (Little Mermaid-based)