Nanker is a joke character with an actually serious idea behind him:

He's an alcoholic bum, with a reason behind the lifestyle, and why it actually, paradoxically gives him supernatural powers.

Nanker follows a rare, suspicious sect of exclusively Dwarven mystics, who focus their lives on overcoming the inherent, Dwarven drive for industrious self-realization through work. This puts them on the fringes of Dwarven societies, makes them particularly disgusting and wicked to their Dwarven co-ethnics, and that's on purpose.

The idea is to utterly debase oneself in the eyes of the community, while at the same time training oneself in the suppression of the working urge Dwarves are born with. This way room is made in one's consciousness to perceive the world more like Humans, and especially Elves do - as an objective reality one is a part of - rather than as a constructed, collective endeavor. As a process that exists independent of us, even as communities, and can be appreciated as such.

Over time this path opens the few Dwarves who follow it to Monkish and Druidic energies that most often remain inaccessible to their kind. It is at that point of the journey that the practitioner is to start wondering the world, and take in as much of it as he can, using these newly acquired powers in the process. Not to achieve anything particular, but to use his newly opened mind to absorb as much of it as he can. The practitioner should also take on an artistic endeavor at this point. But never approach it as work - which he now knows how to do, unlike most other Dwarves - but as pure expression.

The last step of the journey - as befits any classical hero's journey - is to come back home. As something Dwarven society is otherwise very hard pressed to produce: a virtuoso artist of his chosen creative field.