“Second Impact survivor and Nerv's tactical genius — a woman who hides a 14-year-old's wound behind an adult's armor.”
The cheerfulness is armor; the beer is an escape hatch. A survivor of the Second Impact who carries the guilt of simply being alive, and then steps up to lead. She wants to be the most human adult the pilots have — but knows her own wound will prevent her from seeing it through. She runs on responsibility and self-loathing at the same time.