Compound noun or compound adjective?

The Six-o'clock-in-the-Evening-Enthusiastic-Determined-and-Well-Intentioned-Studier-Until-Midnight is a person with whom you are probably already familiar.

I found this sentence in a book, and I am confused about the combination "six-o'clock-in-the-Evening-Enthusiastic-Determined-and-Well-Intentioned-Studier-Until-Midnight". Is it a compound noun or a compound adjective (like in "He gave me the do-it-yourself look")?

I feel that it tends to describe as an adjective would do, but I know that the only case when we have "the + adjective" alone (without a noun) is when we use it for a general category like "the rich", "the poor", "the old", "the modern"..., which, I guess, is not the case here. So what is it?

Solution 1:

It's a noun. The root word is "studier", which is a person. All the rest are modifiers of this noun. It's basically turning the noun phrase

studier who is enthusiastic, determined, and well-intentioned from 6pm until midnight

into a compound word.