Jermielee's "Make Up" starts with a chant-like list of what makeup is meant to cover: bruises, scars, whatever people don't want seen. The repetition of "make up this, make up that" sounds almost like a sales pitch or a routine, which fits the idea that covering up has become automatic. Then the speaker turns, saying "you are already beautiful," and the tone shifts from listing to quietly pushing back.
The speaker seems frustrated, even a little sad. Makeup is called a mask that hides "the real you," and the repeated question "who cares?" suggests the speaker feels that the world pays attention to the surface and ignores the person underneath. The comparison to air and need shows how essential people may feel it has become. The ending is the bluntest part: makeup never helps with your problems and "is never there" when it matters. The mood is plain, reflective and gently protective, as if the speaker is talking to someone they care about.