Attack on Titan (Shingeki no Kyojin) - Levi and Eren. It's kinda sad- if you watch Levi's cloak, it slowly gets bloodier. Me: well very sad at least all episode it turns happy to sadness part, i mean the tokyo goul its makes me THIS IS MADESSS!
Fanfic idea: Eren suffers a major head injury that causes him to regress to the mind of a toddler. He decides that Levi is his father-figure and treats him accordingly. Levi has to put up with it so not to damage Eren's mind further.