Let's see. They appear to look like strange fairies, they have mirror tails, each seem to represent a different element including different flower hats... So, I say, to the left, Saki and, to the right, Gluka. How's that?
I love it! Very, very well done! As far as names... Well, I'm very bad with names so I don't think I'd be much help. What I usually do is type a word that describes the character in to Google Translate to a different language and either keep or alter that word to be their name. ^^
Yep! Like my original manga character. Her name is Hiberna which means "winter" in Latin. Winter, snow and stuff like that have a lot to do with my story and she was also born in December so it makes sense. ^^