It's funny how there's always one idiot in the comments section who didn't bother reading the genres and seeing if it's to their tastes before reading. So for the sake of those still on the fence, I'll lay it out for you.
Please note that this is not Bara. Nor is it a complicated melodrama with cheating and abuse. This is a fantasy manga with a sweet, youthful romance. The characters are all well fleshed out with thier own strengths and weaknesses. The art is gorgeous. The universe is well made and complex. Characters with different power levels shift and change so we see more of their strengths, so if you're reading the first volume and think you have them pinned, you don't. This is a manga with actual character development (I know, it's hard to remember such things exist). At the same time, it doesn't overreach. There was never a point where I struggled to keep up with the characters I was being introduced to or the direction of the plot. It flowed beautifully, none of that choppiness long manga have a tendency to suffer from.
The one downside would actually have been a deal-breaker for me if it had been mentioned beforehand but in the end, wasn't as disappointing as the ending of a similar manga 'Silver Diamond'. I'll place it under a spoiler so you can decide if you would rather be pre-warned or just enjoy the experience.
This is shounen-ai light. Where they basically pledge SUPREME AND EVERLASTING BIG LOVE. But don't do much else. I personally get really frustrated when I feel a romance is being half-arsed and such a warning would have me running away. But in this case I was satisfied enough with how things went.
What it doesn't lack is depth. I struggle to believe the commenter who said that actually read the series at all. Or perhaps they just accepted everything at face value without considering established canon. Whatever the case, it's a real diservice to make such a baseless slur.
That said, the romance is sweet.
The kind where no matter what happens the couple is going to always come together
The couples have their trials and preassures. They have histories that impact their lives. But it still, always, remains sweet. Don't go into this expecting the kind of relationship drama that makes you hate the leads. Go into this taking it as it is, a sweet and idealistic romance. Again, this is a fantasy.
So if you're deciding whether or not to read this I'll say it this way: Do you like fairytales? Much like Silver Diamond, this is a fairytale. And while that doesn't suit everyone's tastes, it is not a flaw in the series that makes it unsuitable. It is simply, your tastes. I personally love fairytales, I love fantasy. And this is why I love reading.
If you've enjoyed Silver Diamond, whether to read this or not should be a no-brainer. They are of similar ilk.
But please don't fault the manga for not being customized to your personal tastes. It makes you look like an idiot. If you didn't enjoy it, say so. But make it clear what is a failing of the manga and what is you.
This is in my top 5 shounen-ai series. It's not the best there ever was but it's up there. I would definitely recommend giving it a go.