Most Helpful Girl
Hmm... If you're looking for something like that, try out Death Note (which is really popular so you may have already seen it), Kamisama no Memochou, Kekkai Sensen, Cowboy Bebop, Black Lagoon, Higurashi, and I hiiiighly recommend Hellsing Ultimate.
Most Helpful Guy
try Noragami (2 seasons), K Project (2 seasons), Rakudai Kishi no Cavalry (1 season), Yamada Kun and 7 witches (1 season), Nisekoi (2 seasons)