Good news! I found a fantasy manga to review this month that isn't an isekai light novel adaptation! The bad news? Well...
STRAVAGANZA (Sutoravugantsu: Isai no hime), by Akihito Tomo. First published in 2012 and first published in North America in 2019.
The young and beautiful Queen Vivian rules over the tiny, peaceful realm of Miteria from behind her majestic iron helmet...that is, when she's not sneaking out of the castle, posing as the commoner "Claria," and getting into all sorts of trouble. Her youthful hijinks come to an end when her kingdom is invaded by the umbra, a race of monstrous, murderous apes. Vivian now must lead the survivors to a nearby kingdom of giants in the hopes that they can find shelter and the assistance she needs to reclaim her land.
Stravaganza is nothing if not a study in contrasts. Udon was right to publish this in 2-in-1 omnibuses because the first volume gives you a very different notion of the story's tone than the second one.
If you went just by the first half, you would presume this was a saucy, largely light-hearted fantasy tale. Vivian/Claria mostly comes off as a scamp as she explores the countryside, gets in a few fights, and ends up nude more often than once. The consequence that Vivian fears is getting yelled at (and occasionally spanked) by the captain of her guard. If I had only read this first part, I would presume that this was just a silly cheesecake-fest and leave it there.
Admittedly, it does (mostly) settle down in that second half. The narrative becomes a lot more linear after that and the stakes become a lot more serious. I strongly suspect that Tomi was taking some cues from Attack on Titan at this point, as this would roughly line up with the time that the anime was getting popular. He clearly looked at that first attack on Wall Maria, then looked back at the giant man-eating monkeys he had already established in his own comic and had an idea. Still, this darker turn forces Vivian to step up as a leader and as a character in general, although she never loses all of her girlish playfulness. The greater emphasis on story means that there is less room for fanservice, although that too doesn't entirely go away either. Still, in a market that's over-saturated with derivative isekai fantasies for teens, it's a pleasant change to read a more traditional fantasy story made for older audiences that isn't a total edgefest.
I was not surprised to learn that Stravaganza was published in Harta magazine. You could tell just by looking at his characters' faces, which have the sort of wide, spade-shaped faces I've come to associate with veterans of that magazine (and its descendant, Fellows) such as Kaoru Mori and Aki Irie. His attention to detail is not as lavish as those artists, but he more than avails himself when it comes drawing fast-paced combat, sturdy castle walls, and lush forests.
That being said, Tomi is arguable more indulgent than either of them when it comes to fanservice. Tomi likes big butts (and boobs) and he cannot lie. He takes every opportunity to have Vivian bend over in ways that thrusts her hot pants-clad bottom towards the reader. When he's not doing that, he's finding new excuses to strip her and tease the promise of seeing more. There's a chapter set at a brother that exists pretty much just as an excuse to show off as many bare titties as possible.
That's not even getting into the giantess fetish material in the second half. While the male giants we see are basically shaped like Shuckles, the giantesses are just big, bodaciously shaped women and Tomi is not shy about expressing desires about being nestled in giant breasts. It's quite shameless at times and one's tolerance for this level of fanservice will likely be the deciding factor in whether any given reader will enjoy this series or not.
Berserk and a little more well-made and mature than your average isekai adaptation.
This series is published by Udon Entertainment. This series is complete in Japan with 7 volumes available. All 7 were published in 3 omnibuses and are currently in print.