What was the name of that anime?!

I only saw the english version but it was funny!. Um, in it there was this girl her dad and her brother moved somewhere new, right!? And they had this cat, and the bro took the cat along with him to school but the sister told him to let it go!. So the cat wonders to the old school building which is haunted or full of demons or something, and the girl and bro and two guys go there to find the cat but the cat has been possessed buy this demon!. And now weird things are happening, like the seven step staircase, the running kid who tried to cut off your legs, and the mirror thing where th real selves were trapped in the mirror and the girl and one of the guys figure this out because the other guy's jacket has backwards words, and there was one about a song too, i think!. I really liked the anime!.Www@Enter-QA@Com

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