There was no doubt that Joy was possessed by Louisa but there was a reason as to why Louisa was released from the realm of reapers.
Since she had already offended the kinodas people first time when everything was happening for the first time, this time , in this time line, she wanted to change everything.
And thus there goes her release story -
'Knock, knock'
Who is it?" said a voice from inside the cabin.
"It's me Clara.", replied a polite voice.
"Hmm? C'mon in.", he said.
It was like a run-down, small rented office. The lady just politely bowed and took a seat.
"Say, Clara, what's up?" his face popped out from the big stacks of piled-up papers.
"Bob, why did you send Louisa to mortal realm?" suddenly her voice turned into a commanding complaint. "Huh? You see, she wanted to see Janice and Noah and everything down there…" he quickly got up and started explaining.