Looking for the name of a 망가 I read as a kid (hoping it's an 아니메 as well.)

There are two main characters, both young boys. They are 수퍼내츄럴 detectives. There is also a sort of school behind all of this where the detectives need to get their licenses (or something like that). It's a light-hearted comedy for the most part.

In one of the episodes, the short boy with black hair gets referred to as a vegetable (turnip??) because of the shape of his head.

In another episode, the taller boy buys a chair which turns out to be possessed 의해 a demon/ghost. He needs to be rescued 의해 the short black haired boy.

Any help would be appreciated, read this 망가 when I was younger in my local library, I've been looking for it's name for almost a 월 now and I haven't been able to place it.