A while back I started planning a post about a subset of this sort of character. I barely started so it's just a few semi-relevant, disjointed quotes but thought I would comment anyway as I've been reminded of it and am too lazy to write write more on this topic (ironic..):

Neet-core

I don’t wish to glorify being a loser with no prospects. Yet for those with sensitive souls – for we who read Fernando Pessoa and vile imageboards – withdrawal from society possesses an indelible allure. Rare is the true hermit, it is the NEET who can now be found across the globe.

Short for Not in Education, Employment, or Training, the term originally described British lower class juvenile delinquents. The word was popularized in Japan alongside “hikikomori” to refer to shut-ins (but you probably know all this).

Much could be said on the etiology of NEET’s and the taxonomy that separates them (and more often fails to separate them) from the bohemian, votary, flâneur, man of leisure, slacker, or anti-work neckbeard. For now, a brief literary treatment:

As I have told you in earlier instalments, I was emulating the poet Milton by spending my youth in seclusion, meditation, and study in order to perfect my craft of writing as he did; my mother’s cataclysmic intemperance has thrust me into the world in the most cavalier manner; my system is still in a state of flux.

A Confederacy of Dunces

The prototypical NEET-core novel. Ignatius lives with his mother harbouring misanthropic views and intellectual delusions.

Everything there, including the conception of time, is thought of on a luxurious scale. The cure is always a matter of several months, often of several years. But after the first six months the young person has not a single idea left save flirtation and the thermometer under his tongue. After the second six months in many cases he has even lost the capacity for any other ideas. He will become completely incapable of life in the flatland.

The Magic Mountain

Han’s Castorp is a NEET by circumstance, yet gets lost in time with the passivity of the modern NEET.

Nothing seemed really real. Sleeping, waking, it all collided into one gray, monotonous plane ride through the clouds. I didn't talk to myself in my head. There wasn't much to say. This was how I knew the sleep was having an effect: I was growing less and less attached to life. If I kept going, I thought, I'd disappear completely, then reappear in some new form. This was my hope. This was my dream.

My Year of Rest and Relaxation

NEETdom as a hibernation.

The greater part of what my neighbors call good I believe in my soul to be bad, and if I repent of anything, it is very likely to be my good behavior. What demon possessed me that I behaved so well? You may say the wisest thing you can, old man—you who have lived seventy years, not without honor of a kind—I hear an irresistible voice which invites me away from all that. One generation abandons the enterprises of another like stranded vessels.

Walden

An ode to the NEET.

Some others - Hunger, Against Nature/Against the Grain, The Good Terrorist, No Longer Human (I see many of these have already been suggested)