I feel like this is one of those things where since it's hentai his behavior is supposed to be an intentional part of the fetish. By normal standards his behavior would be incredibly alarming...but since this is fiction we can ignore the consequences and enjoy the deviance.
Even though her boyfriend gives off bad vibes and sours things a bit, it's kind of cute and funny that Koyori and her friend are so open and chill about the fact that she's a sub in a bondage relationship.
He's just an arrogant jerk but I wonder what her deal is? On one hand she did lie to him about traveling so she's not ready to be open with him, but on the other she could have been telling the truth about wanting to bang a hot guy who hated her - she kept coming back so maybe she really was just kind of a freak who liked having a guy choke her and verbally abuse her.
Aside from her god-tier tits I love Megumi's facial expressions. She just looks so *pitiful*, it does such a perfect job of driving home the theme of how pathetic she feels for letting herself be her students' plaything instead of being a proper and responsible adult, let alone teacher.
Well, she is arguably manic in a depressive sense at least, though that has little to do with the character archetype being talked about. She seems like a sweet and energetic woman but she also had a major depressive episode that made her unable to function all day until her husband came home, and he seemed like he was fairly used to it.
As much as I love manga about bitches getting fucked in every hole and treated like fucktoys, I do actually really like the ending of her saying "yeah not everybody likes that, so fuck off"
I keep coming back to this because the older sister is so hot...aside from the obvious stuff like the big tits and kogal look I kind of love the pubic stubble and that she wears a thong (!) and keeps it on the whole time (!!)