Kyoshiro Okamoto is a college freshman who has a dream to study art in France. Hibiyo Hareluya is the rebellious son of God living on Earth -- a young man who would much rather kick scum to the curb with his fists of justice than stay awake in class. When their paths cross, Kyoshiro gains a protector, Hibiyo gains a magnet for bully activity, and both gain a unique friendship! With God almighty watching his every move and plenty of challenges in his way, Hibiyo will help people accomplish their dreams as fast as his fists can move! Along with Kyoshiro's ideals, of course...
What if roller skates had high power engines that enabled the skaters to do stunning new tricks that defy gravity? What if you saw a beautiful girl effortlessly glide through the air with them? To Ikki, this is reason enough to secretly borrow a pair of Air Treck skates, and step into an underground world filled with gang fights and strange customs. Enamored with high-flying stunts and the flirtatious Simca, Ikki forms an Air Treck gang of his own and starts a life of fighting rival gangs and flying over the rooftops, chasing the girl always one kick ahead of him.
Though Air Gear is focused on a sport of sorts, both it and Hareluya Boy share a similar somewhat campy tone, tons of gangs and fights, and an overall similar mood and feel. If you liked Hareluya Boy, try out Air Gear.
After being placed in a reformatory, Saki Asamiya has only one thing in abundance: attitude. But attitude alone won't help when Saki is faced with a decision: become a cop and help hunt down criminals or watch her imprisoned mother be executed! Thus, she heads back to the crime-ridden school of her past, Takanoha High, only to find that a trio of women known as the Mizuchi Sisters have taken over. Armed with a deadly yoyo and a razor sharp wit, Saki is ready to clean up the school and save her reputation as the number one bully, while hurting the bad guys in the process!
For a much better look at "badass person versus gangs", check out Sukeban Deka. It's a lot more dark, but retains some comedic moments as well. Call it a hunch, but I think if you liked Hareluya Boy, you'd also like Sukeban Deka.