Yami pointed to the unusual mechanism that locked the stall. Rather than just some cut-and-dry bar you slide over nice and easy, it was a rather complicated looking lock that required you to...do...something. Yami didn't know what. He fiddled with it a bit before calling Yugi, but realized this wasn't so much a puzzle as it was a stupid piece of work.

Yugi would know how to deal with it.

So Yami just took the liberty of changing right there, because what the heck they've shared a body for months and months now. Like there's anything new to see.