Got further in The Lost Child (picked up my GS's only PS4 copy to go with the Vita digital).
The dungeons are really lengthy, and the difficulty curve isn't too smooth- by the time I fought the first boss, the basic enemies were doing between 0 and 2 hit points of damage per attack to me (my characters had around 70-90 HP apiece max), but the boss still destroyed me. After doing a round of proper prep for it (leveled up one of the demons I was using, bought more healing items, went to the hot springs for a buff to my characters for the fight), I won, barely.
It definitely feels like a Kadokawa game, for better or worse, in the wonky difficulty and some convoluted systems, but is engrossing if you get into it.