I am turned on by this woman.
Wait, I see you're making a strange face. Let me explain. There's a difference between the Girlfriend of this manga and a typical abusive gf. Look at the actions of the Girlfriend. She writes a note for you so you don't screw up your date. She tells you what you're doing wrong. She plans on visiting you while you're sick.
Unlike irl abusers, the Girlfriend cares for the mc. She doesn't see the mc as some disposable human being that she can leech off of. She needs someone to latch onto. It's just that she also has the irrepressible urge to belittle and humiliate the mc for her own sadistic enjoyment. Sure, this doesn't change the fact that the mc is essentially an emotional punching bag for her, but it's a punching bag that she cares about. It's a punching bag that she is attached to and takes care of every now and then to make sure it doesn't break.
The Girlfriend doesn't look past your flaws. She loves you for your flaws, because she loves humiliating and belittling you for your flaws. But that's still love.
Tl;dr this manga scratches that perfect itch between the overlap of "abuse me" and "love me." The Girlfriend abuses you but she's also attached to you. Personally, a great find.