Sumire, an ordinary schoolgirl who has had the capacity to see ghosts since she was a child, is the protagonist of Venus Versus Virus. When she informs her friends and family about this, they just reject her as a liar. After a random meeting with a broach flying out of nowhere, a monster, and a gothloli-clad monster slayer named Lucia, she makes the life-changing decision to utilize her abilities to battle these "viruses" feasting on the human species.