I'd think you were a parody of the most annoying people on the planet but I know you're not. It's important to gatekeep your hobbies, otherwise people like you show up. Calling anything in this manga "sexual assault" is what makes you sound like a lunatic. You NEED to go back wherever you came from.
Gatekeeping is probably one of the stupidest things that exist. Only reason people gatekeep is because it makes them feel more special. If you actually enjoy and likes something, gatekeeping it is about as unreasonable as it gets. Things you enjoy and are passionate about are to be shared, not to be kept for yourself.
I've been on /a/ for a couple of decades, and the gatekeeping there is probably some of the most idiotic thing in that place. But then again a lot of people on /a/ are elitistic man children that thinks their hobby made them special or something.
Sorry for the rant, but this is something that actually has bothered me for years, and always will.
Don't engage in good faith with people who argue in bad faith
Honestly then you shouldn't engage with nearly anyone on the internet. Nearly 90 percent or something are bots or shills out to manipulate you. Dead internet theory has been real for a while. Especially on the really shitty places like reddit.
They have mutual feelings and have been childhood friends for long, not like I'd condone it but it's understandable banter and love play. The sister is a stalker that would sexually molest and kidnap a total stranger and if the author really planned it to be, stockholm her to reciprocate. I don't get how you can equate this to the main pair.
Funny how the criticism here from other users is that you're a homophobe for calling out stalking and sexual assault between an adult female and a minor, fucking clowns
She's a fox spirit, we don't know how old she really is, but she takes the form she wants. You even saw that a couple of chapters ago.