The sister's reaction is always a rollercoaster of emotions, isn't it? In most stories I've come across, especially in romance manga like 'Fruits Basket' or light novels like 'OreImo,' the initial shock is palpable. She might freeze, her eyes widening as if the world just tilted on its axis. Then comes the fluster—blushing, stammering, maybe even denying it outright because, let's face it, siblings aren't supposed to feel that way. But beneath the surface, there's often this undercurrent of relief, like she's been waiting for this moment without admitting it to herself.
Over time, her reaction evolves. Some stories dive into guilt, others into defiance. In 'Domestic Girlfriend,' for instance, the sister grapples with societal taboos but can't suppress her feelings. It's messy, raw, and painfully human. What fascinates me is how these narratives explore the duality of love and duty, making you question where the line between 'wrong' and 'right' really stands.