jaya's gif

This GIF proves Nya cut both wires

Irrefutable proof! There is no possible reasonable way she cut only one.

Watch closely. Try to pretend you’re holding wires and a shard of glass. Copy her movement. 

She puts the glass knife under both the wires. Then she quickly swings her blade straight upwards in a flash, barely a second.

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But maybe the black wire might’ve slipped when she lowered her hook-hands down,” say some persistent Jaya fans. Unlikely and almost impossible - study them slowly.

The question is, did her choice mean she chose them both, or wanted to cut them both from her life? It doesn’t matter - it’s old news.