The fastest way to get a blackmailer to give up their plans is naturally to change the mindset of the person being blackmailed.
The fundamental reason why blackmailers can succeed is only one: they hold someone else's weakness.
With leverage in hand, conversations with others seem more assertive.
Kohinata Motoyo held sway over Kagura Hikaru's weakness, which was his lingering feelings for his ex-girlfriend Kiryu Hina.
Or should I say, the kindness to protect a girl's reputation.
He was manipulated because of his kindness.
But conversely, if he were not kind or moral, temporarily losing these qualities, then he could completely ignore the leverage in Kohinata Motoyo's hands and break free from her control.
This was indeed a certain way to guarantee victory over blackmail.
Don't care about any compromising photos, let her send them.
Don't care about any hostages, let her tear up the ransom note.
Overcome your own weaknesses and you will be the strongest!