Alopecia

[Rihanna]

An auto immune disorder in which the [white blood cells] are mentally damaged and attack ones hair.
Treatments include [injecting] cortical [steriods] into ones head, putting said steriods on skin in the form of a cream, and cursing ones blood cells for being so stupid.

[Mark Zuckerberg]

The partial or complete absence of hair from areas of the body where it normally grows; baldness.