Only vaguely related, but I think judging from the last couple of eps, that they were thinking ahead of time and changed Tux's mask to the one with the jewel so that it would be easier to stay on his head when he scrunched his eyebrows.
I'm telling you, the jewel in the mask holds the Superglue blob! Which in turn holds the mask to Shibby's face...no, wait, then how does it come off so easily? I thought it looked a little bit cheesy when he held the mask up in front of his face, and then they switched camera angles and poof! It was back on his face! The magic of television, I guess. But it's better than one of the mask get-ups I remember from...the first Sailorstars 'Myu, if I remember correctly. Where the mask is attached to a pair of SUNGLASSES. But hey, as long as it does the job, I don't care how they do it. I'm not all that concerned with straps or superglue and whatnot. I just want to be entertained by the story.