I think MC hypnotized only 4 people, so I don't understand why it have 8 arrows.
If the target does know they are enslaved and their persona and memory is sealed when the app is in use is normal for feelings of hate to stay, and the app probably uses that to punish who committed too many crimes.
The girls have a feeling of gratitude to MC, he did put them under but didn't go too far and helped in resolving a personal problem, so I can accept that they forgiven him for the smoshing.
But still...what are the other 4 arrows? I forgot and MC tested it on 4 other people or is a novel adaptation and at this point of the story he had used it more?