It has a webnovel which is in fact a harem, it's just a well-done harem compared to others since the girls have interesting well-rounded personalities with their own personal issues, good/believable relationships with the MC, and are actually important to the plot. But unfortunately this manhwa is/will be a harem as it follows the original plot of the novel.
Seriously though, you'd think more harems would have female characters like this one, but I can't think of one. I honestly have no idea how authors always write such garbage harems. Don't they want good, interesting female characters? Won't that just make them more likable and the story better overall? I don't understand how people like that misogynistic crap with 1-dimensional female characters that are only there to be eye candy and serve the self-insert MC's ego.
I know everyone is quick to yell harem, but is this actually such a story? At least for me, when it comes to modern harem they're all about 1) sexualizing the female characters, 2) making all important female characters fall in love with the MC, and 3) making all female characters have basically no depth to their character other than being someone who is in love with the MC. This has, in my opinion, none of that. The girls aren't treated as pieces of meat nor are they there just to fall in love with the MC. We are in chapter 77 and so far we have that Harriet has a childish crush on him, Ellen just got to the point where she projects her deceased older brother onto him, and the ex-saintess wants to marry him. The rest of the girls around him are just his friends and guardians. No one is fighting over him. There are none of the cliches associated with harem. If its about not being able to tell who the MC will end up with (if he even ends up with anyone) then ok I get calling it a harem. But this really isn't a harem story. I think it does the characters and plot a disservice to describe it as a harem. That's just how I feel.