Unlike in Kokoro Connect, Youto doesn't even seem to be trying to hide his new found power. Azuki fell too easily to his persuasiveness even if she's forced to lie. It's not like she could say no after what seemed like such a powerful confession. I'm sure he doesn't want to be known as the perverted prince, but it's not like he's suffering from his inability to control himself. This series will work really well as a comedy.
Similar to Kokoro Connect, it seems like their desires are short term and they are unable to control themselves once activatted. Because their wishes turn out to be too perfect, they need to reverse it. It's only natural to want to be want to change when you can't express yourself how you want to, but you only realise you've taken something for granted when it disappears. Youto was unable to bring back his ability to lie because Azuki required it, but once she accepted herself, she was able to give it up.
Tsukiko wished to not be able to express her emotions, but I can't imagine who would need the ability to show what they feel. I'd expect even the most emotionless people would be able to smile because they are forcing themselves to show little emotion. So instead, someone could have wished for a smile.
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