Has Miko Ino's morality been corrupted?

Question

In Volume 16, Miko Ino does and says some things that don't seem to match her rigid sense of justice and morality. In Battle 154: Kaguya Shinomiya's Impossible Demand: "A Cowrie a Swallow Gave Birth To," Part 2, Miko Ino offers alcoholic truffles to her classmates at a party, saying,

"If you want to get drunk for real, you can have some of my whiskey-filled truffles."

When asked whether this is legal, Miko Ino replies with a legal loophole,

"The Minors Prohibition Act forbids the serving of alcohol to underage kids. But food isn't forbidden, so it's legal. Plausible deniability. But please don't have too many."

Then, even worse, in Battle 156: Miko Ino Can't Love, Part 2, Miko Ino chastises Ishigami for not engaging in promiscuous activities with someone who might have been drunk (Ino might not have known this) and who was only willing to engage in such activities out of pity for Ishigami (or rather, she didn't want to let him down or hurt him). Miko Ino says,

"How could you be so stupid?! I can't believe you just ran out of the room and abandoned Tsubame! You chose your stupid pride over... Sigh You're beyond help. You must have hurt Tsubame's feelings. You're a man... Why would you get cold feet? You should have considered how she would feel if you rejected her."

What is the best way to understand these events? Is Miko Ino distraught and acting out of character? Has the craziness of the student council eroded her sense of justice? Or is this a matter of cultural difference? Are Japan's mores so different from the ones I'm familiar with in my own culture that it causes these events to seem strange? I suspect there is a difference in mores, but I've seen Ino complain about illicit relationships , so I'm not sure cultural differences can fully explain this.

Answer 1

Updated Answer

Previously, it was difficult to be sure just what was going on with Miko Ino. An actual answer on whether she was depressed or not was subverted so many times; particularly if it was Shirogane doing the questioning, it would turn out Miko Ino was merely being happy-go-lucky with one of her strange hobbies, and then some ominous foreshadowing at the end would cast doubt on how to interpet what had just happened. But finally, in Battle 190: The Senior Classmate and the Junior Classmate, Part 3, and Miko Ino Can't Love, Part 5, has given a definitive answer that Miko Ino has indeed been distraught over Ishigami dating Tsubame. At the very end, when Shirogane just gets straight to the point (finally) and asks "Do you like Ishigami?", Ino replies with

I... hate him. He isn't serious. He flouts rules. He's stupid. He's not my type at all. But when... I heard he went on a date with Tsubame... I felt a sharp sting in the back of my nose... And my heart hurt. Shirogane... How do I handle this?

Ino is crying in the panel, and this conversation definitively and explicitly proves that Ino is indeed distraught over Ishigami dating someone else, and that is why she has been acting so odd. Notably, it does not explicitly confirm that Miko Ino is in love with Ishigami, and there could possibly be more subversion in the future (I don't expect there to be, but it's possible), but this is also not what this question is asking. This quote definitively proves Ino is deeply distraught, for whatever reason, because of Ishigami dating Tsubame. This answers the question, but I'm maintaining the rest of my answer because it offers additional details I find of interest.

Rest of the Answer

Due to my own lack of knowledge, I can't speak to the cultural differences in play here (though I do think they're relevant), but there is textual evidence to suggest that Miko Ino is distraught over Ishigami romantically pursuing another girl, which is likely making Ino behave strangely.

Though Miko Ino doesn't acknowledge her feelings to herself, it is implied by other characters and by how she secretly assists Ishigami that she probably has romantic feelings for him. For instance, Ino seems to greatly enjoy Ishigami waiting hand-and-foot on her while her arm is broken.

In Battle 158: Miko Ino Can't Love Part 3, there are many implicit suggestions. While talking to her friends, Miko Ino says,

Hey, I've been wondering... How can I explain this...? I've been trying to figure out... How come... Ishigami came over... afterwards, and...

From the text and from the strange look in her eyes, it seems Miko is confused about her own thoughts and feelings for Ishigami. Onondera's response is

"Well... Now's your chance... to make Ishigami your slave. He needs an outlet for his guilt anyway... so it's a win-win situation for both of you."

To which Miko Ino gives an affirmative response. On the other hand, Ino's friend Kobachi Osaragi sees trouble coming, leaving us with this ominous statement at the end of the chapter:

"Uh-oh. This is a bad strategy. Really bad. This is really bad. Miko is... going to realize it soon."

And this is said against the backdrop of a picture of Ino blushing while holding Ishigami's hand as he helps her up the stairs.

There is some textual evidence of Ino being a bit distraught. In Battle 154: Kaguya Shinomiya's Impossible Demand: "A Cowrie a Swallow Gave Birth To," Part 2, a dismayed and worried Ishigami notes,

"Damn it. She looks desperate for male attention."

Further proof of both Ino being distraught over Ishigami courting someone else and of her having romantic feeling for Ishigami is in the same chapter, when she slurs these words:

Why are you alwaysh... so mean to me? You don't talk like that to anyone elshe... You always, always, always look down on me! I hate you sho much! But you're nice to other people! Be nice to me... like you were at the culture festival... The way you're nice to Tsubame...

Here, she explicitly names Tsubame and indicates jealousy of the way Ishigami treats her compared to Tsubame. This would seem to indicate that she probably likes Ishigami herself, and that she's feeling out of sorts because of Ishigami courting Tsubame.

Answer 2

Supplement to other answer:

From the bonus chapter Ch281.1: