Thread:Misry6/@comment-39509676-20190518191838

I got an entry, that could at least explain the troll's behavior.

I found Minerva's entry before it was revealed, she had a terrible past and then redeemed herself.

"While Gemma of the Guild Sabretooth is a nasty customer, his daughter Minerva eclipses him in evil and has her own plans.One of the first things she does is torture Lucy in one of their tournament matches, right in front of everyone after she had basically already won. When Lector is seemingly killed and Jiemma is injured, she reveals she saved Lector, but then holds him as a hostage to get Sting to do what she wants. She then kicks her possibly fatally wounded father out of the guild, for being too weak, which is the philosophy he had been following. In the last match, she holds Millianna hostage to make Erza and her friend Kagura fight each other. When she loses, she leaves Sabertooth and joins a Dark Guild. When she runs into Erza, who's been turned into a child, she tries to kill her in revenge despite Erza being a helpless little girl at that point."

One of her atrocities gets negated once it's revealed her father is/was a jerk.

I also found these lines on TV-Tropes.

Moral Event Horizon: I could argue several lines could get axed there, because some actions are proven to be not completely irredeemable in-universe. 
 * The vicious, near lethal beat down that Minerva gave Lucy in Chapter 291.
 * Ziemma crosses it twice. The first is when he orders Yukino to strip in front of all of the Sabertooth members and erase her guild mark,and the second one, when he erases Lector for no reason other than he bore the Sabertooth mark on his body. Considering that the rest of the guild was shown smirking or smiling even during his previous antics, their expressions at this wanton cruelty might signal that Ziemma may have crossed the line even in the eyes of many of his subordinates.
 * Pretty much everything Minerva does is a candidate. The aforementioned beatdown of Lucy, blackmailing Sting with Lecter's well-being by promising to return Lecter only if Sabertooth wins, and more recently, taking Millianna as a hostage to provoke Erza and Kagura. It seems she is fond of escalating this to the point of audacity given she also stabs the latter In the Back while they were off guard for the point gain. The worst bit: Erza and Kagura were settling their differences and about to reconcile. Finally, she revealed that while Erza and Kagura were fighting, she tortured Millianna just For the Evulz, gloating about how pleasant her screams of pain were.