Serial Killer

I live in a place with many others. The house is divided into levels and we each have our own section in which we stay at all times. But every so often, someone, usually from the top level, is taken away. They never return.
My best friend is my next-door neighbor, his name is Jack. We live on the third level of the house, the highest level which still has people. Everyone from higher levels have been taken away.
"I wonder what's out there that makes them not want to come back," I said to Jack.
"Yeah, me two, it must be wonderful," Jack replied, " I can't wait to go!"
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