It’s an intense shower routine (due to the stereotype of black people being dirty) that includes something like 5+ steps for an “everything” shower. One example is using an African sponge net to exfoliate, body scrub, body wash, shave, douche (😔), dry your skin, neutral body lotion, scented lotion, body oil, powder, perfume, then proceed with the rest of your morning routine.
The stereotype of black people being dirty stems from antebellum slavery propaganda that black enslaved peoples were backwards and barbaric, and their dark skin tone is from years of rolling in the mud like pigs (this is just one of the anti-black stories peddled at the time). This sentiment then spread into the 20th century, which is when the majority of specifically black women began to uphold extreme cleanliness habits such as bathing with bleach, douching, and skin lightening
Mothers taught daughters taught more daughters, to the point of today, which is where the black girl shower now lives, significantly much safer (although douching is still prevalent). A sort of counterculture then evolved to point the finger at white people who proudly proclaimed that they let water run down their legs, deeming white people as dirty. Globalization has now exposed us to realizing that it is much more normal to shower twice a day globally than just once.