Zenkonyado
After nojuku, here is a new article in the series where to stay during the Shikoku pilgrimage.
Definition:

Zenkonyado (善根宿) are places to sleep provided to Shikoku pilgrims by private individuals free of charge or for a very modest financial contribution. This may be a room in their home, in a small separate building, in a converted garage, or sometimes a building constructed for the sole purpose of lodging pilgrims.
It is an honor to receive Shikoku pilgrims. It is a form of o-settai. A gift.
Practical information:

It is not always easy for a non-Japanese-speaking pilgrim to find a zenkonyado. A list does exist, but in Japanese. I will attempt to translate it for you. Furthermore, it is strongly recommended to confirm by telephone, as some locations may no longer exist.
One last detail of importance: these are often small rooms where only 2 or 3 people can sleep.
The simplest approach is to ask at the temples whether there is a zenkonyado along your route. I also advise you to memorize the kanji well so you can recognize the building that serves as accommodation.
It is difficult to know what you will find. It could be a new, relatively isolated building as in the first photo, still under construction in the summer of 2015 at the expense of an individual to “keep busy in retirement.”
It could be a simple room beside a national highway, full of... cockroaches, as in the second photo. And even more improbable, in the shape of a... bus.
Sometimes the owner will take you to visit the surroundings or offer you a small snack. One thing is certain: you will be sheltered from the rain, and sometimes you will make surprising encounters.