Or maybe a "hello sister", because they certainly look a lot alike
As for me, I'm puzzled by all the "racism" comments about the "foreigners".
What I saw was actually a complete reversal of every "foreigners" clichés we can see in animes, and the jabs were only directed, from my perception, at japanese bias and preconceptions themselves.
The big black guy match was the perfect example : he's seen as huge, threatening and different by his opponent, and when we see through Tsukuba eyes, that's how he's shown. But everything outside Tsukuba perception show him as being just a karuta lover, happy to play and looking incredibly nice and gentle.
So yeah, what I saw mocked here were the japanese typical expectations and related behaviours, and the very opposite of racism.