Rise-chan wrote...
Episode 4:
[spoil]I was dumbfounded when Jirou's sister made a happy face and started fighting with a bear.... I was like, "Are you fucking crazy?", I did knew that she was a crazy fighter and all, but didn't expect her to be THAT crazy of a fighter. This episode showed me why I should NOT like her, while it also showed how much she really cares about Jirou. I really didn't like it when she just saw the bra and then barged into the bathroom saying "Who's
swindling my brother!", now, why should it be any of her business when her brother does ANYTHING with another girl? *sigh*
Sorry, just didn't like it is all.
spoil]
You seem to have trouble understanding characters, resulting characters that you can't understand = don't like.
Once again it's simple:
[b]Why would she challenge a bear?
Because she likes to challenge herself, and that's one of the more positive traits she have. You would probably react the same If she's challenging a Full grown Pro Wrestler despite her size and age. Challenging a bear is simply as anyone using "IT's OVER 9000" in their sentence rather than to use "A lot"
Why would she be angry if her brother is with another girl?
Because that shows she really does care for her brother. She was already traumatized by the loss of her father a prominent male figure in the family. Of course Jirou would be the next most important male figure to her. Jirou getting a girlfriend means her relationship with Jirou will be less closer and currently she doesn't want to lose him to anything, girlfriend or even death.
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Understanding a character needs to be deeper than skin deep.
So, you need to try to see the reasons and intentions in their actions.