How to get more companions?
The two easiest ones are Prihxa and Sapphirine
Prihxa can be found in any dungeon by going to a ? space, then release her from the cage
Sapphirine you need to go to an alter (random overworld location), push the gemstone in then feed it
The other two that are currently available are related to clearing quests in the shop so they take longer
That one is from Lurra in the Shop, however on some of the earlier versions the Quest is a bit buggy from what I've read, you need to except the quest, beat a Cow Farm, then on the same cycle find the location Lurra mentions (reshuffling the world seems to break the trigger for it to appear, not sure if that has been fixed yet, but it won't be for older saves)