Tear Jerker / Superman Reborn

• Despite his sometimes malicious intentions, Mr. Mxyzptlk has a pretty sad moment after being captured by Mr. Oz. He's confident that Superman will rescue him, but time passes. His frustration grows, and finally he comes to a sad realization. Despite all their history together, Superman doesn't care about him. Though in a case of irony, due to the fact that he usually spends his time in another reality, it's likely Superman wasn't even aware he'd been captured.
• Superman and Lois (the rebirth/pre new 52 ones) slowly losing the memory of their son.