I understand it was a bit too much, there's more better ways she could've handled it without physically hurting MC. I think she though it's just easiest way to bring MC unconscious since DIKs needed all maggots to be tied to a chair. Otherwise I don't think MC would have let that happen so easily being aware of what's happening. In the end it would have happened anyway, just would have been more troublesome for DIKs. (Still a DIK move though.) I wonder how Derek was brought in and who did it. I don't recall if it's mentioned in game.
Yes, she's an interesting, diverse character even more so than others so far, we see some sides of Quinn which are all not bad. About that punishment you mention, I don't see it as a punishment, more like a lesson. MC has to get used to a harsh reality that not everyone is as nice as others and deal with it. I understand it can be irritating, but the sooner MC understands it, the better it will be in the future.
Also, here's my tier list. I always seem to be asleep when all the fun happens.
If you're wondering why watermelon is in S tier. That's because I love watermelons, but not in a way you probably thought.
