Lucy Hale, Ian Harding Lucy Hale, Ian Harding

Nobody knows what it's like to be in a relationship that's so wrong, yet so right, more that Pretty Little Liars' Ian Harding. Playing the adorably handsome, yet morally conflicted Ezra Fitz, Harding says that although there are legal ramifications for him and his student Aria (Lucy Hale) to be together, they're soulmates.

But the couple may run into some major problems. A cop saw Aria leave Ezra's apartment in last week's episode and a mystery person took the key Aria uses to get into her boyfriend's apartment. Harding tells that viewers might be focusing on the wrong thing, how Ezra's former fiancé could be returning, and why fans might be upset with him by the finale's end. Plus: Which PLL would Harding's high school self have dated?

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It looks like the cops may be onto Aria and Ezra's relationship.
I love that's what everybody is concentrating on. I think it's going to make for a good surprise because the cops are there, but for what reason is still a mystery. Whoever lifted up that mat is also going to be surprising.

Is Ezra's prior relationship going to come back up?
I really hope so. The actress who is playing Jackie, Paloma Guzman, and I went to college together. I got a text one night saying, "They want me for possibly a small part on your show and it may be recurring." She could be sticking around for a while because there was a discussion of where to live in Los Angeles.

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What kind of reaction do you get to the "Ezria" relationship?
For the most part people are rooting for it because they realize it's not a gross thing. In terms of the physical and adult emotional part of the relationship they're moving at a snail's pace — I think they're only feeling each other up — and I think ultimately they're soulmates and people are realizing that. But it's a little weird sometimes. I was in New York, in a restaurant, and a [girl who was] very obviously a teenager came up to me and gave me her number and I was like: No! As soon as we left, I trashed it. They're assuming I'm this person in real life.

Will sex eventually come up between the two?
I think it will come up and once it does it'll be done in a way that's very tasteful and sweet. It's not like, "Yeah, now it's time!" These two people absolutely love each other.

Besides having an underage girlfriend, does Ezra have any faults? The guy seems perfect.
I think he is honestly a great guy at heart and tries to be this upstanding character. He's a very logical guy and tries to make sure everything is kosher and I think that's why this whole relationship with Aria has thrown a wrench in his life's spokes. He wants to be the golden boy, but there are certain moments in his past that are not the brightest and most shiny. I would love to see more of that because being such a good guy gets boring.

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What advice would you give to your high school self?
I would tell him to chill out. I took a lot of things really seriously and I'm not saying be lazy, but know that the stakes ... like getting into college, are not life and death.

Which of the four main characters would your high school self date?
probably would have gone for Aria. She's unique and has the whole short brunette thing, which in high school is all I dated. I think I would've been driven to how creative and artsy and well-spoken she is. Shay Mitchell's character is pretty awesome, too I just think the whole lesbian thing would've thrown a wrench into the relationship.

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You did a web series called Hollywood is Like High School with Money. How did that come about?
I got a call saying the people over at Alloy wanted to give me the part. I'm a firm supporter in work begets work, so I said yeah let's do that. If it's a cool project — let me be pretentious for a second — if it speaks to me, then, yeah I'm going to do it whether or not it's a web series, a $100 million film, or a TV show that only has a million viewers. It's easy to get caught up in the career mindset, but I'm very content on just working on good stuff.

Give us a final tease for Monday's finale.
People are going to be angry at Ezra because there's going to be some words that were not spoken to Aria that she's going to be pretty [angry]about. There's a picture online right now of me from the season finale and if you look closely I'm in Aria's bedroom, which I've obviously never been in before. I'll leave that for the viewers to salivate over. There's also a very awesome moment in a bell tower.

The Pretty Little Liars finale airs Monday at 8/7c on ABC Family.