Copywriting:
What did I do, you ask?
I killed her, she was the only friend I had in this city with whom I could speak the truth.
Do you regret asking me?
No, I don't regret the sin I committed.
You ask me why?
Because I am still alive, I still have the possibility of getting true love.
You ask me why I laugh?
I laughed at myself for not understanding her before killing her, and why I didn't pay attention to the window earlier...
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Concept: In an era of overwhelming desires, who can be alone?