Severus snape: veiled destiny at hogwarts

Severus Snape goes back in time to 1967, now a 7-year-old. He directly approaches Dumbledore, revealing everything. In response, Dumbledore provides him with a new identity and a job – the Defense Against the Dark Arts professor. When Tom applies for the position in 1968, Dumbledore informs him that the job is no longer available, preventing him from placing a curse on the position. Severus, armed with his future knowledge and powers, assumes the role of the Defense Against the Dark Arts professor.

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Authors note- So I was testing Chat GTP to see how I could use it to help me create my fanfic, so here's the result