This game is cute, I like the concept and the art/music/etc were nice.
Resetting for only one scroll each time feels maybe a bit slow, and I was disappointed to see that it didn't seem to reset the Yokai behavior at all (unless I misunderstood) -- it might be nice for each reset to feel like a bit of a breather, especially since I thought the Yokai felt to be a little overwhelming after some time.
Maybe it would be nice to have more upgrades, related to the Yokai behavior? For example, maybe an upgrade that changes the mechanic so a mouse HOVER over the Yokai would send it away - that would help clear up most of the frustration and anxiety (since multiple could be sent away with no worry about the overlapping hitboxes) while still keeping the same need for players to balance between both dimensions and stay on top of things
Also the ability to swap dimensions another way (space bar, RMB, idk) would be a nice QoL thing, although it might break the current balancing which is based on moving the mouse to the top right each time. Unless I totally missed something that already exists for that
Overall it's a nice game and very unique. Good job!