Looking for the name of a komik jepang I read as a kid (hoping it's an anime as well.)

There are two main characters, both young boys. They are supernatural 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 oleh a demon/ghost. He needs to be rescued oleh the short black haired boy.

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