>>21853041I'd love something a bit lore focused, like a "Mumei adventure journal" where it tells a story of her going on a journey through a bunch of diary entries and illustrations made by Mumei herself.
A reversible plushie (the kind you can turn inside out and have a different design) would be cool, one could be Friend and the other could be Mumei's cursed Hooman design.
Some kind of subtle shirt/hoodie would be great, Mumei's color palette is pretty subdued so you could pull off a cool piece of clothing with some runes and a feather motif and not have it be too "anime".
Literally anything with Azure-papa's art on it would be top tier as well.
Mumei confirmed that a daki isn't in the works (though she said she would consider doing a cursed daki at some point), so the best "fanservice" merch I could imagine would be a cute voice pack of going on a date with Mumei in the city or something.