Ugh, I really didn't want to go deeper, but you leave me no choice.
Due to Jax's appearance in the game, it's safe to acknowledge that he is of the "African American" Black race. According to the United States Census, this constitutes as "a person having origins in any of the Black racial groups of Africa. The Black racial category includes people who marked the "Black, African Am., or Negro" checkbox. It also includes respondents who reported entries such as African American; Sub-Saharan African entries, such as Kenyan and Nigerian; and Afro-Caribbean entries, such as Haitian and Jamaican."
With that said, here is an example of a male, like Jax, that fits that mould:
View attachment 8131
Now, let's take the offspring of a couple where both the mother and father fit that mould:
View attachment 8133
Here's another:
View attachment 8134
Now, lets take the offspring of an African American and another race. Here's what you'd get:
View attachment 8135 (African American and Louisiana Creole)
Another:
View attachment 8136 (African American and Caucasian)
By looks, what would you attribute Cassie to more?
I never once said that Cassie is not black, but at the same time her features make her look like she's of mixed race, not FULL AFRICAN AMERICAN, as defined above. Again, that doesn't mean she's not "black", but at the same time, she doesn't look fully "African American".