I never noticed that. I only ever saw the metallic clasp, but the red thread slipped my eye.

After thinking about it, though, I suppose she's only doing it for fashion. Remember all the times she's worn crosses? They were very in style for a while. Meanwhile, much like 90-some-odd percent of Japan, Ayu is probably agnostic, not Catholic. It's not a very religious nation at all, and Kaballah probably has next to no presence there. She probably saw Madonna wearing it, and thought it was cute.