The Magical Girl Big Sister is a Pervert [Short Story]

My sister became one of the magical girl battle squad! A big sister quietly watches over her brave fighting sister from the shadows. However... the big sister is actually a perverted stalker who's obsessed with her sister! From loving her sister so much, she's somehow acquired the ability to fight evil monsters hand-to-hand on equal footing! She might even be a yandere! This is a love story where such an abnormal sister dotes on and cherishes her cute sister to the fullest.