^ OMG so cute!! hahahaha...

i dunno what causes it but it seems to be common in Malaysia. once they turn black/dark grey, it seems to be kinda hard for them to turn back white/light grey. i bought mine from the pet shop when she is little. she was light grey. almost white. but after a month or so, she turns BLACK. =.= and never change back. i tried to put her at colder temperature but it doesn't work. she is now a year plus already.