Watching Ed (Cory Michael Smith) kill Oswald (Robin Lord Taylor) was like witnessing one of the worst breakups you can imagine -- which is saying something for two people who weren't really dating. But that's exactly how the last episode of "Gotham" played out, with Ed taking vengeance on his one-time best friend for killing the woman he loved.

What are Ed's feelings for Oswald? It's been made clear that Oswald is in love -- or at least thinks he is -- with his fellow villain. But are those feelings reciprocated? According to Smith, not exactly. But while Ed had made it clear he doesn't have romantic feelings for Oswald, that doesn't mean there's no love there.

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"It was his best friend ever. He was a mentor, he looked up to him. I think he saw Oswald as a senior to his freshman," as the actor described to us at WonderCon. "I'm learning so much from you... But also there was some confidence that he gained early in Season 3 when he realized I know Oswald so well, I can manipulate him a little bit to help him see what he needs. He really was a great number two for him as Mayor: He did the work, set things up."

While Oswald wanted more, Ed wasn't on the same page -- and that crushed him, to the point that he lashed out, brutally. And that's what makes us question whether his feelings were true love to begin with. As Taylor previously told Screener, he doesn't believe Oswald has the ability to know what true love is.

"He wants true love, but he wants it the way a robot cyborg wants it: Oh, look at that behavior. I want to do that... But without actually knowing what it is, and truly understanding it," he said. "In that sense, he'll never know true love -- because it's not that."

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Regardless of what Oswald actually felt, it's all for naught now. Oswald crossed a line when he killed Ed's girlfriend, and it's an act the soon-to-be Riddler isn't going to get over.

"There was really a beautiful relationship there," Smith says. "Then Oswald had to ruin it, by stealing love away from him."

"Gotham" returns Monday, April 24, at 8 p.m. ET/PT on FOX.

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."