In a bizarre fantasy world, students known as meisters are trained at the illustrious Shinigami Weapon Meister University; but the tools they wield are no ordinary weapons! Each meister is paired with a human-like being who can transform into a weapon at will; and after defeating a pre-kishin - a human whose soul has darkened - the weapon eats the soul within it. A meister's ultimate goal is to collect ninety-nine pre-kishin souls and one of a witch so that his or her partner will become an all-powerful Death Scythe. Maka and her partner Soul Eater; Assassin Black Star and his partner Demon Blade Tsubaki; and Shinigami's son Death the Kid and his partners the Demon Twin Pistol Thompson Sisters each vie for their ultimate goal, but plenty of challenges and adventures lie in their way!
Magico and Soul Eater are rather different, but if you liked the art style in one of those, then you ought to check the other one too. I believe that in this case, the art style is enough a reason to write a recommendation.
Honoka Takamiya is a typical teenager; he does his classwork and admires Ayaka, the school idol, who sits next to him in class. But the boy's life changes forever when one day, a piece of the school falls on top of him and he's saved by Ayaka due to... her magical powers?! For Ayaka is a witch, and deeming Honoka to be 'her princess', she is determined to keep the boy safe from harm. Now Honoka must try to stay alive while countless other witches target him, learn more about Ayaka and her craft, and still try to maintain his school life in the process!
Both Magico and Witchcraft Works feature a normal human protagonist within whom some secret power is hidden and a powerful mage set on protecting him\her. Also both of those manga feature some subtle romance. Last but not least, the genders are reversed: in Magico the "damsel in distress" is female and her protector is male, but in Witchcraft Works the first one is male and the second female. It's quite possible that you might like one of those if you liked the other, so give it a go.
A girl gets attacked and is clueless why, but a man shows up to save her from trouble and proposes to her. Such fairytale-like scenario wouldn't look out of place in shoujo manga, but the thing is neither Magico nor You no Ou is a shoujo manga. Needles to say, if you liked one of those two manga, the other one might be right up your allay.