Big Brother, Can I Be Your Servant?

If you could see how much every girl liked you, who would you check first? Choi Won-seong chose the campus belle he'd had a crush on. Her affection rating: 2.5. Species: nonhuman. Before he could process this vital information, he found a homeless vampire girl by the roadside. And that wasn't all. The girl called over her best friend, too. Their reason: his blood tasted good. Choi Won-seong: “…” Two girls in flowing white dresses stuck to him all day, calling him “big brother” over and over. All they did was suck his blood. And suck his blood. Unable to take it anymore, Choi Won-seong kicked them both out. But the two of them crouched downstairs, crying and pulling up flowers and plants. The landlady caught them and insisted he take them back in. Just then, the System told him: 【When the vampire girls' emotions fluctuate, you receive money as a rebate. The more nonhuman species detected, the higher the rebate multiplier】 And so, a poor student and two vampire girls moved into the luxurious residence known as Biguiyuan Yufu. That very day, he asked the orphanage director to help the vampire girls enroll in school and made them his personal attendants. The director of Beishan Orphanage, where Choi Won-seong had grown up, had always treated him like her own son. Because she was such a kind person, he got curious and checked her affection rating for him. To his astonishment, the orphanage director who had treated him like her own son since he was little wasn't human!!! 【Affection rating】: 90.1 【Species】: nonhuman