Literally the second season of JIN. Just focuses on his internal struggle and how with every life he saves he could be causing someone else to fall in their place, or only prolonging the inevitable.

Both have to deal with an older guy having to disguise themselves as high school students to fit in and end up changing their school environment as well as themselves. Plus it's extremely hilarious! Like seriously there was not an episode that I did not start busting out laughing while watching it! It's great!