I haven't read the prequel manga, but I don't think I missed much.

This manga started off rather poorly. It had elements of comedy/manga/harem, and didn't really do those well. Even the ecchi elements weren't all that well thought out.

But somehow in the ending, the writer really shows how well he could have done this manga if he'd bothered to flesh out the mecha, the aliens, the rest of the world, basically anything, the same way he fleshed out characters in the ending.

At the end, you felt such a strong emotional tie to everyone that it was hard to let the series end like that; you wanted to see more of it, it just somehow felt incomplete.

Without the ending, I'd have given this manga a bare 2/10 stars - counting just the ending, it'd be about a 7.5/10 stars, so we'll say an average 5.5/10 stars all around.

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In a world where troubled young hearts are besieged by evil spirits, only one can wield love as a weapon: the God of Conquests, Keima Katsuragi.