filth teaches filth.

well, the questions is what do you need to consider them as lovers? this show isn't the romance genre, so you could go that therefore it doesn't have a love line (not a traditional one anyway). do you need a love confession where it is literally spelled out? a kiss, sex, or anything of the sorts to tell you directly their relationship is romantic or sexual or both? if that is what you need to define two people as lovers, then they probably aren't in the canon narrative of the show.

to me, they are soulmates, twin flames, anything else you could put here. they are it for each other, the only other person in this world who understands the other and who cares about the other and who inspires every possible feeling of the human condition on each other. they change each other's lives when they meet, their lives become so wholly interwoven that there are significant before and afters in their respective lives because of each other. their first scene in the rain (and the ep8 addendum) in front of the hospital is literally called the confession scene by show writer kim.

they were teacher and student. they are diametrically opposed, they are the same, deokhee is seok and seok is deokhee, they metaphorically have the same dna in their brain, seok's happiest memory is of deokhee, deokhee's happiest time in his life with seok, she saves his life, he only wants to be killed by her. they murder for each other as a mutual sign of their devotion and their care. seok hated deokhee with a burning passion for six years because she revered and was obsessed with him for all the time before. deokhee thought her brain was perfect the moment they met. when asked, deokhee laughs off that she wasn't in love with him but with his brain. seok outrightly calls herself his. deokhee never declined that he loves seok, no, he just kept a tail on her for six years. deokhee thought of himself as a singular genius until he met seok. his death was supposed to be her victory, his final gift to her. she gifts him more life because after she got him back all she wants is for him to stay. no one gets to open deokhee's skull but seok. seok only ever wanted to surpass deokhee, never anyone else.

Jeong Se Ok + being obsessed with Deok Hee

"Why do you keep asking the professor to give you all his stuff?"

So, Doctor, why did you kill Kim Myeongjin? Do people like us really need a reason?

I would have killed that guy too.

He had his eye on you. His eye on me? I don't get it.

So to keep her at your side you made her hate you, and she cut you with a scalpel, and she strangled you, and she BEGGED you on her knees in the rain to keep teaching her, and you had her stripped of her medical license, and worst you turned her away and she HATES you. But you never hated her, years later you can't help smile as you see photos of her, and you track her down and tell her only she can perform the surgery to remove the tumor in your brain, and you shut down her pharmacy, you kill her dogs, you make her life a living hell, and you also keep the police off her scent and you kill for her, because she's YOURS and you're always so surprised when she's EXACTLY like you are, so much more than you want to admit, because you flinch at the darkness in yourself, but she lives without shame.

And she SEES you, she sees all the ugly parts of you, that you're a killer, selfish, an egomaniac, and she doesn't flinch, she celebrates, and she cries and says she'll do your surgery because you've lied to her, the cancer is terminal and you're dying and no surgery will fix that, but this is the last lesson you want to give her because she wanted everything. And there's nowhere higher for her to go, she's never failed a surgery, so she needs to now, your brain open to her blade, because nothing will push her like your death to greater heights than either of you could achieve. And she hates you, screaming and crying and asking why do you hate her so much, because the only reason you could leave her is if you HATE her, and you ask her once again, when have you ever hated her? And you beat her, and berate her, and everything you've done is for her, because you are the same, you're the same.

And what if she agrees to do the surgery, your way, with all of your conditions met, and just like her maybe you want to die in the OR as well, and you've done everything in your power to give her an impossible task.

And what if she saves your life?

It had to have been just like mine.

Imo their relationship being platonic made perfect sense for the story's chronology. Deok-hee takes his job as Se-ok's teacher very seriously - to cross that line would be a violation of what she asked of him as her teacher. Much of their conflict is because they're no longer teacher-student (their relationship was already evolving by the time she tried to strangle him) - and Se-ok has already moved past the need for him to teach her, while he clings to it. His demand that she opens up his brain is both fitting and ironic - he rejects her, then demands she enter the most intimate part of him (the brain has a pulse like a heart). He even twists up that demand by turning his surgery into a highly convoluted plot where he dies dramatically in the OR by her hands, his final, parting lesson that perfects his student. If the show had validated him, I would've been so let down. I think that now that Deok-hee has to face her after she entered him, their relationship is going to get a lot more fun - no more barriers between them.

BUT…

I love how the show is centered around Seok, and her life during and after her time as a medical student. Focusing on her relationships, friendly and professionally, that she’s had after her experience with Deokhee.

Seok is a fully developed character. She wasn’t hung up on Deokhee after The Incident, aside from her trauma over what happened. She wasn’t thinking about him every day. It was clear she was caught off guard by his call when he contacted her.

But it’s EXTREMELY obvious that the same could not be said for Deokhee.

We see him as a medical professional. And as a student, just like Seok. We see him with his assistant Ms. Ra, the only real personal relationship from the audience’s perspective, and it’s very vague.

The only thing we know is that Deokhee has thought about Seok FREQUENTLY since their fallout. And he harbors no negative feelings for her. In fact, it’s obvious that he thinks of her fondly, based on his reserved smiles when reminiscing of her.