This work's theme is "adults with chuunibyou".
"Chuunibyou" is an easy word to toss around, but understanding that as a motif isn't so simple. I think the source of it is how people tend to think of their childhood as embarrassing, as part of how they progress from a state of innocence to adulthood.
In becoming an adult, one becomes different from their past self, and in that same vein, different from those around them. As a result, they think for no reason that they're an utterly unique individual.
If you consider it this way, "Agh, my cursed right hand is~" or "I can whisper into your mind~" and so on aren't really the core essence of chuunibyou.
The true nature of chuunibyou is the heat of life.
It's an explosion of one's imaginative power.
It's a form of resistance against a chilled society, wielding both purity and creativity.
Lately, I've been thinking: how can I maintain my chuunibyou until the day I die?
If I can do that, I can enjoy sake for my whole life.
https://en.touhouwiki.net/wiki/Dateless_Bar_%22Old_Adam%22/Story