Exorcism without repentance can backfire badly
(check out what Jesus to say about the evil spirit returning to its former habitation.)
Not good.
100% correct, the demons take 7 more demons who are more evil than themselves back into the person. And that cycle repeats, if the person lets their guard down after being exorcised (this also applies to people who by the grace of God are able to cast the demons out without a formal exorcism). So that’s now 8 spirits cast out who could then take 56 (8 times 7) even more evil spirits into the person, and so on.
Matthew 12:43-45
43 “When an impure spirit comes out of a person, it goes through arid places seeking rest and does not find it. 44 Then it says, ‘I will return to the house I left.’ When it arrives, it finds the house unoccupied, swept clean and put in order. 45 Then it goes and takes with it seven other spirits more wicked than itself, and they go in and live there. And the final condition of that person is worse than the first. That is how it will be with this wicked generation.”