Which free five star??

Sooo who do I choose for the free five star?

Nilou C2

Chiori C2

Varessa C0

Clorinde C2

I have Nefer C0R0 - Lauma C1R1 - Columbina C0R0 - Nahida C0R1

Chiori and Nilou are two of my favourite characters

I have a full team for Varessa

Clorinde has her weapon...

I really don't know who to choose...