Goes to show that Hibiki is the real lady among the sisters.
Hibiki doesn't drink coffee, she drinks canned vodka and/or bunker fuel. Besides, depending on the artist, Ikazuchi (AKA "Loli Okan") and Inazuma can also be the "real adult". (In fact, anyone but Akatsuki, who is portrayed as a child even in the ones where they're all 25 years old.)
Hibiki doesn't drink coffee, she drinks canned vodka and/or bunker fuel. Besides, depending on the artist, Ikazuchi (AKA "Loli Okan") and Inazuma can also be the "real adult". (In fact, anyone but Akatsuki, who is portrayed as a child even in the ones where they're all 25 years old.)
Basically, irony at work. Akatsuki is the one who (based on her in-game quotes) most desires to be seen as adult, so she's the one who doesn't get it.
