This character is known as v1 Nami, story-mode Nami, or just story Nami.
Be careful when evolving her for the first time. Her final form, Nami Thunderbolt Tempo, is junk. So is Nami Tornado Tempo. What you want is Nami Mirage Tempo with her useful special. After you get one Nami Mirage Tempo, other Nami's can be either evolved to Mirage Tempo as well (for raising skill levels),or just used as sockets for your favorite Nami.
Update: following the introduction of super-evolved Nami Thunder-Breed Tempo at the end of her chain, you'll probably want to finish this chain and super-evolve at least one of your Namis.