For over two minutes, we were given a glimpse of new magical beasts, new characters, Newt’s next adventure and the biggest surprise of all – Nagini.
For those who aren’t familiar with the Harry Potter universe, Nagini the Snake is actually one of Voldemort’s hocruxes and his ‘pet’ snake. And a hocrux is an object which a dark witch or wizard keeps a fragment of his or her soul in order to attain immortality.
No one expected that Nagini was actually a person until the trailer came out although fans have long speculated it.
Everyone had no issues with Nagini being a person, but it seems that people are upset over the casting choice.

South Korean actress, Claudia Kim was chosen to play Nagini the Snake. A lot of fans weren’t happy about it; claiming that J.K Rowling was trying too hard to be inclusive and diverse in her casting choices.
The Naga are snake-like mythical creatures of Indonesian mythology, hence the name ‘Nagini.’ They are sometimes depicted as winged, sometimes as half-human, half-snake. Indonesia comprises a few hundred ethnic groups, including Javanese, Chinese and Betawi. Have a lovely day ?
— J.K. Rowling (@jk_rowling) September 26, 2018
J.K. Rowling took it to Twitter to explain Nagini’s origin after a fan called her out for making it look like an "afterthought" by casting Kim. The critically-acclaimed author went on to say that Nagini was inspired by a “snake-like mythical creatures of Indonesian mythology.”
Ummm....Isn't it better to stick to topics you actually KNOW something about...namely Muggles and Wizards..instead of making a complete fool of yourself??!! Being a writer, least you could do is some basic googling before confidently sharing ignorance!!?https://t.co/TcxEvlGfhr
— Rita Singh (@Rita_2110) September 27, 2018
Some were also offended that Western producers are viewing Asians as one-dimensional, and all Asians are automatically of Chinese descendent/looking.
Ceritanya diambil berdasarkan southeast asian folklore, tapi pemainnya pake east asian. Memang orang asia wajahnya sama semua gitu ?
— langit (@lordpolarsky) September 28, 2018
And her "comeback" to someone saying she made Nagini a Korean woman to retroactively make the franchise more diverse was just?? As you already said, if Nagini really is based on Indonesian mythology, then it still makes zero sense to cast a Korean actress for the role
— Calo ︽✵︽ (@Nightstrike15) September 28, 2018
This #nagini bit is so stupid in the first place. I mean, why was this never revealed before??? In the HP books? It's too weird of a coincidence for it to be included post-HP book 7 just so casually. We deserve more explanation.@jk_rowling
— abdulwasay (@awa7ayb) September 28, 2018
Well, to be honest, if Nagini has Indonesian origins, they could’ve casted someone who looked more of the part, perhaps an Indonesian/Malaysian/Singaporean/Bruneian or someone with a Javanese ethinicity.
Jadi menurut Acha Septriasa yang pernah ikut casting utk peran Nagini di Fantastic Beasts ini (yes she did ?), mereka sengaja cari aktris yg berwajah Asia krn mmg inspirasi Nagini berasal dr mitologi Kalimantan. pic.twitter.com/aaeRxZMR65
— dyan (@dyansaptr) September 26, 2018
We also found out that Indonesian actress, Acha Septriasa went for the casting of Nagini based on her Instagram post in April.
It's too late to cast another person at this stage, so we hope moving forward the producers would be more considerate on their choice of casting and stop trying to Whitesplain things that they lack knowledge in.