I'm also curious about the story behind Meari's wallet. Is it just the size that makes Him a go mad or is there some other emotional significance to jt?
It's because Hina recommended that Maeri buy it.
Hina was also the one who first got Meari into
papakatsu, but scoffed at Meari refusing to do "adult stuff". Hina has to let herself get fucked by all manner of old(er) men, even the quintessential 'fat ugly bastard' types, just to make ends' meet, and
then her host "boyfriend" takes a cut and asks her to keep going to pay for him and his lifestyle.
Hina's burnt out, hates what she does, hates the feeling of being trapped, and hates that Meari never went as far as she did into the business--and she hates that Meari now has a rich lady who seems to have taken a liking to her, shelling out tons of cash without Meari having to "put out".
And, Hina hates how innocent Meari still is, and maybe most importantly she seems to hate how kindpy Meari treats her, and how much she considers Hina a friend, to the point she holds her opinion in high enough regard to have purchased a wallet on her recommendation and continued to use it despite it no longer being practical.
Hina has a lot of self-hate, and she's projecting that onto Meari. The wallet was a tangible target for that hatred, as it also represented a common tie between them. By stealing it, Hina breaks that link, corrupting their friendship--and my guess is she does
that because a part of her recognizes Meari to be too pure to remain around her, and is trying to push her away in that self-destructive sort of behavior people can fall into in those headspaces.