Yeah, it might be something like that. So that they don't just fall off all the time. You might be a more advanced model than I was!

[Nano reaches out, gently grasping Xion's second toe between her thumb and forefinger and squeezing at it from both sides.]

There should be a click or something...

[She tries it a few more times in several places from the base to the tip. Hopefully Xion's not ticklish or anything.]