End of story.
Within minutes, her friends swarmed. “Toxic.” “Block him.” “Who hurt you, bro?” Then Katya herself typed: “Alexey. Don’t do this here. You’re embarrassing yourself.” crime and punishment.vk
Then he deleted the draft.
It sounds like you're asking for a short story based on the title — blending the classic Dostoevsky theme with the aesthetic of an old social network (VK, popular in Russia and Eastern Europe). End of story
On the seventh night, he opened a new post. Private. Only visible to himself. Don’t do this here
“Yes?”
He typed: “I killed Katya Sokolova on October 12. I used a letter opener. I staged her phone. I posted as her. I am Alexey Morozov, and I am rotting inside this browser tab.” He stared at the blinking cursor. Then he changed the privacy settings to “Only Me.”