This was an interesting episode in that it showed that Oga actually had a caring side to himself. Then again if anyone paid attention at some point he stopped trying to pass off Baby Beel onto other people. Oga accepted the fact that he would never get rid of him and accepted that parenting role. In this episode he was shown as caring for others beside himself or Baby Beel. When Kunieda was trapped in Hecados’s grasp all he could think about was rescuing her. He also get perturbed by the injury that Hilda sustained.
I think that more should be done to show that Oga is actually a very human person. I think it has already been proven that he is not just some uncaring person. Oga was actually beating himself for letting Kunieda getting caught and letting Hilda get injured. He made a vow to become stronger so that way he could protect those things that he cherishes the most. While this is theme is very overused in anime again it has the effect of breaking down Oga’s apparent inhumanness.
The only thing that I did not like is Oga’s refusal to train with Saotome. He based this upon pride. More like he got a feeling that Saotome was looking down on him and thus he wanted to show Saotome that he could become stronger without his help. In this case it would be very wise for Oga to take the training that Saotome is offering because Saotome has actually dealt with demons. I have no idea if Kunieda’s grandpa has. I do believe that eventually Oga will get that training from Saotome even if he does not want to.