If you liked the Busou Renkin manga, the Anime-Planet community thinks you'd like:
Ichigo Kurosaki is an average high school boy with a not-so-average ability to see spirits - something that hadn't affected his life much until a strange woman entered his room one day. Named Kuchiki Rukia, she's a shinigami who was sent from the spirit world to destroy a hollow - a dead-soul-turned-monster; and much to her surprise, Ichigo can see her. When the hollow suddenly attacks his family, Rukia intervenes and is injured in the process, leaving Ichigo to fight it himself. But when Rukia lends him her shinigami powers - which is forbidden - he inadvertently drains them away and has no way to return them. Now, Ichigo is a full-fledged shinigami who must juggle his studies with his newfound duty of fighting hollows; but having gained his powers through forbidden means, the spirit world isn't going to leave Ichigo alone. Ichigo and Rukia must keep their situation a secret from the other shinigami, or the consequences could be dire.
Action and comedy with fights a plenty, both Busou Renkin and Bleach contain enough of your daily recommended dosage of spiky-haired heroes with their illogically large weapons, and magical powers that they get from a female fighter of their respected professions. Both toss a serious salad every now and then but still play the comedy angle more often than not.
Rin Okumura is a seemingly ordinary boy living at the Southern Cross Boy’s Monastery. One day, however, Rin encounters a boy who has been possessed by a demon. Amidst the struggle, he not only awakens latent powers sealed within him, but also learns that he is the son of Satan! No longer able to stay under the protection of the church and with his very existence straddling the line between human and demon, Rin decides to fight against his parentage and joins the True Cross Order as an exorcist. Now, the teen must attend the True Cross Academy and begin special exorcist training alongside his new comrades all while keeping his identity a secret; but can the son of Satan really become a true exorcist?
The main characters of Blue Exorcist and Busou Renkin are both a little clueless, but at least they're committed to the fight. Kazuki and Rin cause some problems for the people closest to them, but in the end, these guys really are valuable allies. If you want a shounen series with action and a clueless main character, you should be able to chuckle at either of these.
Haru Glory lives peacefully on Garage Island with his sister. One day, Haru fishes a strange dog-like creature named Plue out of the ocean, and soon after meets its master, an old man named Shiba. With this man comes terrible news: the world is in peril, for the evil organization Demon Card is attempting to conquer it with power-giving stones known as Dark Bring. To combat this threat Shiba has spent much of his life fighting back with Rave, a Holy Bring; and the Ten Commandments, a sword it powers. When members of Demon Card arrive at the island, Shiba discovers that Rave and the Ten Commandments will now only respond to Haru, making the young boy the new Rave Master. Armed with newfound power, Haru and Plue set forth to put a stop to Demon Card.
If you like the classic shounen set up: strong, young heroes, a cute female sidekick, and an evil organization to fight, Busou Renkin and Rave Master should both fit the bill. Kazuki and Haru fight villains of all kinds, from the deadly to the... oddly designed. So long as comic relief villains don't bother you, you'll be fine. ;)
Power granted is power to be abused, except for both series' the power is used for justice by the protagonists. Hints of romance, more on comedy, action and super powers, both shounen series focus on the fun stuff more than the serious. Also noted is that Rising x Rydeen is the more perverted of the two. By far.