On the outside, she looks like an office secretary with an extremely sweet appearance, but Kang Bit Na is an extremely talented judge. After all, that's just her appearance. In fact, Kang Bit Na comes from... hell, or you can also consider her a DEVIL. Kang Bit Na's main mission is to send bad people to hell, whether they directly or indirectly commit crimes, leading to the logout of others. Then one day, Kang Bit Na met the talented and also very gentle and friendly detective Hang Da On. However, Hang Da On has some private worries that are difficult to talk about. Luckily for him, life with Kang Bit Na has made him a lot better.