it has nothing to do with "romanticized rape", rather that some other's go in one of two ways when depicting rape unfortunately. "Romanticizing" as you pointed out or "sensationalizing" to enhance its sexuality.The author admitted themselves they enjoy drawing sex scenes especially, so showing rape is an easy way of accommodating her tastes. It doesn't make the plot any better by having every male character raped, that's an artistic choice not a plot choice. They don't have to have Taehoon raped, what exactly does it add to the plot. We know the priest posses his victims by raping them, that makes sense. We know that Leo was raped to later had issues with sex, that makes sense. If the author wants to just explain that Taehoon accidentally falling in the lap of a rapist adds anything to the plot besides giving Leo to get over his loneliness quicker that's just plain lazy writing.
That’s exactly the point. The author has free reign to draw as much sex as they want. They’ve just chosen it through the medium of rape which is unnecessary because it’s already obvious this is a mature content plot involving sex. Sex will happen of course, so then what’s one less forcible sexual encounter?

If the author want a rape in her/his story, as long as he/she explaines that that's not something right, i don't get why some of you scream about it.