Curse Breaker (or how to find answers)

"What are you doing here, in the middle of the night?" James asked.
[...]
"I'm doing research on a curse, okay? That's not your business Potter. Go back to your room."
"A curse?"
"Yes," Regulus said, smiling arrogantly, as if he expected James not to know what he was talking about anyway. "The Cysgu Curse."
James stayed silent for a bit.
"A sleeping curse?" he asked, wondering why Regulus was interested in some welsh curse, or whatever.
Regulus looked at him in disbelief.
"How would you know it's a fucking sleeping curse? Do you know anything about it?"

Or 6th year Regulus Black is trying to break a curse casted one millennium ago by a welsh wizard, and James just happens to know a bit of Welsh thanks to Remus.
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English isn't my first language so if there's mistakes, tell me!
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