I think this is a language barrier thing. In Japanese for example "Josei Manga" (lit. "female comics") is a completely acceptable term. One of the largest comic publishers in Japan is called "Shounen Jump," with shounen meaning "boy." It is similar in Chinese manhua (which this app seems to be based of but for a western audience). Every manhua app will first ask you if you are interested in girls or boys comics. For example the home screen of BiliBili Manhua has "女生" (girl) and 男生 (boy) as separate tabs (out of only seven total tabs with the others being like new, trending etc.). It is really more of describing a specific genre than about who is 'allowed' to consume it.
More good background. I know that in California where I live, it’s becoming less popular to explicitly divide things by gender, so that might explain why some people have a negative reaction to it. I can understand that some other cultures have more strongly defined gender roles.
I can see how women might consume more romantic fiction as comics/stories than men, though if there's nothing in your app that's only relevant for women, I'd recommend dropping that as part of your pitch
labeling it as "for women" is wise, because that makes it acceptable. the media is fuming, stomping their feet and foaming at the mouth about generative AI being used by men for what little sexual gratification can be obtained from low quality slop LLMs and image generator produce.