Warning: This post contains feminism!
It seems in every fandom that the audience has to make the main two girls, or side girls rivals of each of even if said girls have no rivallary what so ever to speak of.
One example is Bleach, the main girls Orihime and Rukia are always pitted against each other in fandom (Mainly for shipping reasons) despite them being friends in canon the closet thing to a negative emotion is Orihime’s admitted jealousy. However, there relationship is from negative with Rukia openly encouraging her to get stronger.
The fandom in many areas is drawn into Rukia vs. Orihime lines, and this is not the only example. Even girls that have never spoken to each other are still pitted against each other like Sakura and Hinata.
One of the things is that often the loudest supporters of one of the girls will be vocally anti the other girl.
Another trend is dividing this into a girly girl vs. tomboy debate and arguing that their less preffered girl is worse or unlikable for side she mainly leans too. This does not happen with males. Ichigo is openly tough and tries to show little emotion while Ishida is stotic, but he also has traditionally feminine hobbies such as sewing and knitting.
The fandom does not vermantly hate either of them for their differences and both are loved without rasing an eyebrow. Mind you the girly vs, tomboy thing is also extended if both girls lean on one side. Exaamples are Orihime and Rukia. I would argue both of them are on the feminie scale, but in different ways.
Rukia is more elegant and mature femininty while Orihine is more innocent and childlike femininty. On the opposite end is Korra and Asami from Legend of Korra.
Fandom seems automatically pit the girls against each other instead of excepting a friendship, the Naruto fandom was for months salivating over a Karin and Sakura catfight that *spoiler* never happened and Sakura ended up saving Karin’s life.
What causes this? Is this a result of media for decades only seeing women as love intersts and rewards for the males, and we still subconsciously see them in those roles.
An extension of the competitiveness that girls are pressured to do against each other? I still remember Lauren Faust talking about the importance of having a show with girls encouraging each other and not competiving against one another