Kio is the most likely V kid to get missing since Urere can teleport back to V at anytime, Ano's solid light hologram body can reform at any place inside the SKI mansion, and Kaden is just too smart to go missing.
Kaden: o.o I agree. Urere: x3 Yes! Ano: *nods* Kio: *falls back down to earth finally, crashing into the mansion* Well.. o.o I always wanted a skylight.