[Mouri narrows his eyes. Of course it wouldn't be so easy.

Instead he directs it to everyone]

There's no mistake there was a pen in the Game Room at some point before Sonozaki-san died, but nothing like that was found there. The culprit must have taken it away with them, but why?

It's just a pen, I doubt anyone would have thought of comparing pens to that tiny piece of metal.

How can a pen have taken part of anything in this murder?