Roxas would try to talk sense into Saix because seriously, if he wants to get inside that badly, that's what portals are for. But luckily Axel opens the door to let them in.

"...hey, Axel," he says, feeling about as weird addressing Saix's body that way. He steps inside, but looks back at Saix with a frown.

"You could've just said. This whole bodyswap thing happened before." He didn't have to try pretending to be Axel. And in retrospect, it seems like a really weird thing for Saix to do. What was he thinking?