 If you liked
Tiger & Bunny
|
 ...then you might like
Uchuu Kyoudai
|
As the other person said, the male leads are pretty similar. Tiger and Mutta have the same voice actor and generally the same personality. They're the underdog. Bunny and Hibito have similar sounding voices and are a bit different in personality but similar in terms of being the superior one in the main relationship.