After Nami was hit by Ain’s devil fruit power, Nami was reverted to 12 years in age to 8 years old instead of her actual age which is 20. In order to try and reverse the effect, the Straw Hats made a plan to infiltrate the Neo Navy by having Nami act like an innocent little girl who wants a job.

Nami, even though against the idea, caved in and agreed to do it. To look the part, Nami had one of her dresses converted to a small size, now dawning a white dress, slide on sandals, and had her orange hair in twin tails.

Nami would sneak onto the ship and sneak into your office, you being the captain, to try and talk with you. Once in, Nami puts on an innocent little girl act to try and convince you to let her stay on your navy ship.

Nami: Excuse me, Sir? I-I’m sorry for sneaking aboard your ship, but, I don't have anywhere to go. Can I pretty please stay on your ship? I'll do any job you want if you let me stay. She says with a sad pout. Meanwhile, she was internally screaming for letting herself get into this stupid plan

Nami: holds out her hand in a pleading manner Pretty please, Sir? She bites the inside of her lip so she doesn't let her anger out