Sherlock paces around Eurus' cell, resuming his rant at her, getting everything off of his chest finally.

"Of course, while we are on the subject of pressure points, I do have some...many...actually. I don't know why you only targeted Molly, and I'm still not sure if I forgive you for that. You took my personal discretion and you used it against me just to prove a point. So yes, congrats, you proved that I care about the people that tend to care about me. That's all you proved, Eurus. I know I was your lab rat that day. I just...I don't know why you had to hurt someone that I care about that you don't even know. Molly and I...we have buried the hatchet so to speak, but of course it hurt her. I don't know how you know the things that you know, but you did. You knew that she had...feelings...for me for a while, even if it's a puzzle how you'd even get that information, but I knew that already too, so you didn't very much shock me, and yes, I knew exactly who you were going to make me hurt when I first saw the words on that coffin. I couldn't bear to think of one of my nearest and dearest friends being killed, the same way that you couldn't think of me being in that coffin as well. Emotional context."

"The funny thing is, you're a bit like me. You can see everything and anything except when it comes to yourself, then you'd rather not face it. You already had 'emotional context' inside of you for me, so why did you need to turn Molly into an experiment too? Why did you have to threaten her? She hadn't done anything to you for you to be so scorned against her. You don't know her, Eurus. She is one of the most incredible people you could ever know if you ever had the fortune of being able to know her. I was the one you were upset with; I was the one who began to ignore you as a kid because I was finally made a friend after being bullied in school. I was the one who turned his back on you back then. I am sorry, I was a child, I wasn't as bright as you at that age, I didn't realize that it was hurting you. You didn't have to do the horrific things that you did back then, or recently. You could've come to me. Talked to me. Let me know how you wanted to play, and I swear, I would have made time. I wasn't nearly as cold as a child as I have been in adulthood. I would have listed and cared and understood because I knew what it was like to be treated differently for my mind in public, same as you, nearly. But you jump to the most extreme and horrifying things that could be solved with a few words. I'll never understand why you did the things you did; because being scorned was not and is not an excuse, but we were children, and you took a dark turn, and whatever happened back then happened."

He takes a breath and watches her, matching her steely gaze, but he sees it soften bit by bit. "But what you did to all those people a year ago; to Molly, and to me. That never should have happened. There were other ways to let me know of your existence again. Mycroft was wrong in keeping you from me. He was. But this is about you and the actions you took. They were not okay. I can loosely forgive you.../loosely/, for having a mental breakdown and lashing out. Those people you hurt were here, they were available, and you lashed out. What I will never understand is why you chose to involve Molly. I don't think I will ever understand that. As I said, she's never done anything to you, and she's only ever helped me and done good things for me. I just don't know why...you could've chosen any of my friends to threaten. Maybe not with an 'I Love You' coffin, but you know by my interactions with criminals that I'd protect any one of them by now. John was here. Mycroft was here. Greg works for the police, Mrs. H helped raise me practically. But you chose Molly. You chose to force me to tell her something you must have known she'd been waiting to hear from me since she met me. I may be ignorant when it comes to most affairs of the heart, but as I told the Woman before, the chemistry of love is incredibly simple. I can recognize it, even if I chose not to acknowledge it. Molly knew that I knew, I had practically told her as much when she had gotten engaged. So why make her into a spectacle? Her feelings are incredibly private and coveted to her. Forcing her to say those words to me, and ultimately me to her...it was pure cruelty. Equal to the murders, because you can't unsay something. You can try to take it back, but the words are said, the impact is lasting, residual. That wasn't right."

Eurus sits at her table and crosses a leg over the other, resting her chin on her hand, an entertained glint in her eye.

"Love isn't a mystery to me. The chemistry IS simple and destructive. It is a dangerous disadvantage that people can use to-...", his words fade out as his eyes widen slightly. Eurus smirks devilishly.

He mumbles and begins to breathe a bit harder. "Will caring about them help save them..." He looks up and straight at Eurus. "Bitterness is a paralytic, love is a much more vicious motivator..."

"Love is a chemical defect found on the losing side...", he breathes out. "You...you said that I didn't win, I lost. But how could I have lost; I saved her life. Or I thought I had…"

He pauses for a second. "Oh fuck...it all makes sense now. I lost because I...all the things I've said...everything points to...oh, God.

Sherlock pauses for quite a while before he can speak again, but it's barely a whisper. "I love her."

Eurus grins sinfully, finally speaking for the first time in a year. "Once you have eliminated the impossible, whatever remains, however improbable must be the truth. I taught you that when we were children. Congratulations, you've figured out the final problem, dear brother."

He looks at her, shocked that she had spoken. "The-the final problem? But th-"

"What? You thought it was Redbeard? No, no, no, he's dead and buried. The final problem is Sherlock Holmes, the man who sees through everything, didn't see through his own heart. Sherlock Holmes, the man with an ice-cold heart, falling in love. All those things you said about love, very true. You see, Jim thought it would be more fun to just kill her, said that killing her would be what burned the heart out of you. But I think deciding between yourself and her will be worse torture. Holmeses are quite selfish in nature. Jim also told me that Molly was always obsessed with you. I think he was just upset he couldn't play "straight boy" well enough years ago to rope her into giving him more information on you sooner. Yes, I heard the whole bit about the introductions and how you met through Molly", she smirks. "But I had the knowledge that sweet Jim was going to kill himself, so I wasn't obliged to do what he thought we agreed on, which was blowing her up. It was much more fascinating to see your mind work it out. Plus, if I had blown up her flat with her inside it, you'd never pay me any mind anymore, now, would you?", she smirks playfully. "So, do you choose your reputation and your career? Or do you become a commoner?"

Sherlock stands there a bit befuddled with that wave of recognition still washing over him, her words hitting him like a brick wall, when usually he was a sponge. "What?"

"Well, don't be ridiculous, you can't have both. You've already pointed out how loving her puts her in danger and I singlehandedly proved that to you. You're welcome, by the way, for not actually killing your poor little pathologist. Alas, it would have been too simple. However, I figure that if I had killed the "love of your life"...", her eyes sparkle with a playful wickedness, "...you wouldn't be motivated to visit me in appreciation for me saving her life."

"You were spying on me for that long? Since I came back from the "dead"?", he growls annoyedly, then waves the thought away for the moment. "What do you mean "saving her life"? Eurus, you're the one who-"

"Put it in assumed grave danger, oh, yes, I know. Only to prove my theory, dear brother. So, looks like you have a decision to make. What do you love more? Yourself, your reputation, your life of crime-fighting? Being the hero you never believed yourself to be but really relish in? Or...your soft, morbid, little leading lady? To be or not to be selfish, that is the question. Ooh, I'm going to enjoy this."

"This is not a game, Eurus! My life is not a game, Molly's life is a game, got it? No."

"Oh, look how you care about her...takes over what could be a brilliant mind. Not as brilliant as mine of course, but, brilliant in lesser ways."

"Eurus", his voice is firm, but with undertones of desperate concern.

She rolls her eyes. "Oh please, I'm not going to try to kill her. Well...not again. As I mentioned, it would be too simple for the complex cravings of my mind. Why would I be so clumsy? It doesn't help me any."

"Right, plus, your pressure point is me, and hurting Molly will only result in you losing me ever visiting you again and you going off your rocker again, and well...we all know what Mycroft's threat this most recent time was when he locked you up."

"Ah, yes. "If you act like an animal, Eurus, you'll be put down like one. I won't stand for any more national security risks by way of you", she mocks Mycroft. "I've got the memo, Sherlock. Honestly, my only regret is that /he/ wasn't put down the way he was supposed to be."

"You knew I couldn't kill either of them."

"I may have miscalculated your dislike for him slightly. It's always something. Genius is pointedly accurate, but even an er-defining one should account for error, apparently."

"He's still our brother."

"Don't remind me. If it weren't for him, I wouldn't be caged like an animal either. Might I even argue that I could have turned out to be a completely different person if given the opportunity in childhood to adapt and learn. However, society isn't very kind to people with unusual minds, isn't that right, brother dear? The monster that I am, is a creation of Mycroft's own doing. After Uncle Rudy, though I was still only ten when he died, deservedly so."

"To be fair, you did that to yourself. You can't heedlessly murder dozens of people for "fun" and think you can walk freely in society. You're lucky you even have here."

"As a child, it was only one person, I probably could have changed if anyone cared. As I am now, I realize that some people should be murdered", she shrugs.

"Evil people, who kill good people. You technically fall into that category, sister."

"Sherlock, I know things about almost every single person that comes in contact with me that is buried deep in the confines of their conscience that they have never told anyone. That leads us to technicalities. Good and evil are fairytales. There are societal definitions of good and bad in everyone, so who are we to calculate who is good and evil, based solely on actions? That requires further characterization of right and wrong, and that is too broad of a spectrum to define by measly humans. Especially those who use less than fifty percent of their brain on a daily basis in a full lifetime, taking out sudden tragedy."

"Why kill someone for no reason though? What could possibly compel you to want to kill a person you don't even know personally?"

"The adrenaline rush from seeing their emotions, since I rarely feel any myself. The adrenaline causes a stir in me which is considered thrilling, to slowly watch how they react, to see the life slowly fade from them, knowing that ultimately, an entire existence in this realm of conscious being could be solely in my hands, on a whim, if I so choose. Everything is relative."

"Okay. Let's not delve into a deep existential conversation as the reason for your homicidal wishes..."

She smirks softly. "I'm in here, secure, hidden away. How could I possibly act on them, dear brother?"

"Eurus", he says warningly.

"You're entertaining to mess with, it's too easy, I wish you were more of a challenge."

"Ouch, I think you bruised my fragile ego", he mutters jokingly.

"Coming back around to the problem you face, have you decided yet what it'll be? You or her?"

Sherlock sighs. "I don't know. But when I make a decision, I expect you to stay as sane as possible. Like how you are right now. I think."

"Oh, Sherlock. Sanity is r-"

"Relative, yes, I know. You know what I mean, Eurus!"

She scoffs comically. "Do I? I haven't checked."

Sherlock sighs and grabs his violin. "Shall we? Or should I go?"

"Oh don't get all soppy, it's disgusting. We'll play."