I think it was the first victims tongue he cute off.
But didnt they sew it on?? Kind confused now
It's the gum from the blond guy prior; it's why he gave it in as evidence after talking about the blond bully. It's wrapped in blood cause he had hit him with a needle on the head and to minimise the bleeding he used paper; the guy who now cannot speak had his tongue the hold time, but it was ripped severely due to him biting it so the doctors resowed it back together
The shoe-boy bit his own tongue when he was so badly beaten. So technically Namsoo didnt cut it off.
OH okay
Sneaker-guy's tongue.
But what was the thing in the paper ?