Help me find the name of that anime!

ok, i cant remember the name for one of the animes i liked most...

i cant remember much it was around in 2007..

i remember that there was a group of people who live together/in the same building, and they were like friends, but everyone had a secret identity and was a super hero of something like that, and they were enemies (as heroes) and i remember that there was a tall and had blond hair (unsure of the color)(adult maybe) with a whip weapon, and a teen boy who is the main character..

and i remember a fighting scene that took place in tokyo's river (lots of anime has that river)



it was like a comedy action anime. and the drawing style was something like Fruits Basket, it wasnt bloody as much as i remember.

basicaly it was a anime about group of neighbours/friends, who were secretly heroes and enemies as heroes, no one of the other knew about it.



i hope i remembered it correctly and i hope i got enough info to find it!

THANKS!! ^^

Help me find the name of that anime!