Emo Xiansheng Bu Kepa

A sly demon that attacks x An earnest angel. As his job to fulfill people's dreams, the angel Nuoqiu took on the peculiar job of becoming a demon's private investigator. The demon kept claiming to have known Nuoqiu for a long time. But angels and demons aren't suppose to have anything to do with each other? As they get to know each other, the more Nuoqiu felt like this demon is different. "It's as if... I'm actually starting to like him?"

(Source: Kuaikan, translated)