The confession scene in ep 6 is … everything to me. I have seen it far too many times. I don’t believe perfect things exist.
Yet, for a first kiss in a BL drama, this comes as close to perfection as I have ever seen. It touched something deep inside me, and from that moment, I knew this drama would hold a special place in my heart forever. I don’t know if I can do this moment justice, but I want to try. Also, I have a few (hopefully interesting) things to say about the translations of the original Chinese dialogue. ;)
(It's long, brace yourself)

Let’s revisit this together. :)

To set the scene, emotions are already running high. Both want to protect the other, no matter what. Shu He by wanting to send Zi Ang away, and Zi Ang by staying by his side in order to protect him. 

The theme of hurting someone to push them away as a means to protect them is not new, many shows, movies, novels etc have something similar, and yet I think the way the dialogue flows in this scene is in a league of its own. 

Every time Shu He tries to push Zi Ang away, Zi Ang pushes back. 

(Also wanted to mention: I love how Shu He grips the blade of the dagger that Zi Ang gifted him (which is Zi Ang's motif), while he says: "Having you by my side is the biggest danger to me. Look - the tighter I hold it, the deeper the wound." )

And every time one of Shu He's arguments is rejected, Shu He reaches further into his arsenal, so to speak. And every time he does so, he becomes more personal, and every time he reveals more of himself.  

All these things that he has not told Zi Ang so far (such as the fact he wanted to use him as leverage against Prime Minister Gu, that he knew Gu was the mastermind behind the massacre on the Duan family, or that the poem and the mementos of their time together were fake), and which may also weigh on him because Zi Ang has not known the truth until now. 

But again, Zi Ang is having none of it - "since you want to use me, why are you still pushing me away?" Getting right into the heart of things, aren't we? Zi Ang can see right through him.

The dialogue up until now was already good, but from here on out until we fade to black in a few minutes it is getting even better. But you've all seen it, so we all know what's about to come - :)

Foreshadowing, poetry, the most romantic lines to ever grace our ears. 

However, the lines that Zi Ang says immediately before their first (and second) kiss(es), made me lose sleep. 

And one of the reasons was they made sense, but at the same time they didn’t? 

While the show was airing, I had the impression that they were at least as much foreshadowing, as they were related to what happened up until this point.  but I couldn't quite put my finger on it, as I hadn't seen the entire drama at that point. 

Did anyone else feel the same?

Zi Ang says, "我心甘情愿当这个替死鬼." Translated as "I'm more than willing to be the scapegoat."

Scapegoat as translation never quite set right with me. To me, scapegoat is very much connected to taking someone’s blame for them. However, Shu He was never blamed. So I looked into the word, 替死鬼ti si gui, and whether the translation is accurate. And it is, for the most part.

However, in Chinese, ti si gui carries a slightly different feeling – its more about the sacrifice, (so Zi Ang saying he will suffer (or even die) for Shu He, and not so much about being punished.

So, what Zi Ang is saying is more anlong the lines of 

“I would rather die for you than live without you.”

“If death is what it takes, let me be the one.”

After all, he has just drunk the (swapped out to be water, but at this point he didn’t know it wasn’t poisoned) wine meant to as a punishment for rejecting to kill Shu He, so this is not metaphorical – it’s a declaration of love stronger than survival.

After they kiss, the perfection continues, with their breathing telling us how fast their hearts must be beating at this moment. (Masterful acting by both of our beloved actors!)

Zi Ang studies Shu He's reaction and wants to kiss Shu He agian, but he pulls and walks away. Not because he doesn't want to be kissed again. But because of everything it might mean. and how he will invite vulnerability and possibly heart-break. One last act of defiance. (haha, how he can’t get away!)

But again, Zi Ang won't let him go. 

He stops him, to which Shu He is now willing to "remove the last layer" so to speak. To ultimately reveal his most vulnerable inner self, as if he were standing naked before him - he pulls off the bandages from his hand and shows Zi Ang how his brother had taken away so much from him. Crippling his right hand forever. The hand he uses for writing poetry and playing zither. (And here's my personal interpretation of this since the first time I saw that Shu He's hand was crippled) - like a bird that had his wing broken. No longer able to fully perform the arts he loved so dearly - he will never fly the way he wanted to. 

Zi Ang is dismayed, rightfully so. 

Shu He: "Back then, I couldn't protect mother. Now I can't protect myself. I can't protect you either." Shu He showing all his flaws, crippled hand - and Zi Ang only asks whether it hurts... T_T
Zi Ang tells him he will protect him with all he has. Of course, these words break down Shu He’s walls. To me, the turning point is Zi Ang saying “you are too hard on yourself.” 

But Shu He wants one last confirmation - does Zi Ang share his dream for freedom? 

You know which line is coming...

Zi Ang: "山河万里只有你才是我想要的自由。

By the way, at this point I have to point out the poetry of Chinese language and the dialouge again. I’m sure many of you have seen both translations of this sentence by Zi Ang? The more literal (as on YT) and the more interpreted one from Gagaoolala:

Gaga: "in this vast land…
YT: "Ten thousand miles of mountains and rivers…
… you are the only freedom I want."

but Chinese really shines in the beauty of their characters – simple somehow, yet every Character is a picture, so in a way I feel it is almost a painting:
山 = mountains (shan)
河 = rivers (he)
万 = ten thousand (wan)
里 = ancient measure of length, approx. 500 m (li)

God, who doesn't love that line? I’ve seen so many comments on how this is the most romantic line in (BL) history, and I have to agree. Maybe you can apprechiate it even more with the Chineses character peotry behind it. ;)

Anyway, let’s continue:

Shu He's answer was kind of odd in comparison. “Don't let me lose again.” Or was it just me who thought so?

Mi Jin said in an interview that “Shu He just had to say something sarcastic” – maybe, yeah, a little bit, but I think it’s more than just that. I think it's all in design, so let's revisit. 

Shu He: 别让我再输一次。 

Don't let me lose again. 

Again, I'd like for a small revision – because in English,  “to lose” is too broad of a meaning – (in English you can: lose a person or an item). This is not true for shu  输. Shu in Chinese refers to games, competitions, bets.

Therefore, a better, less ambiguous translation would be

"Don't let me be defeated again". 

If we're going back to the motif of “Go” or “playing games” for Shu He, to me this symbolizes Shu He playing greedy. 

And he says so later, that he ("I wanted too much" - Ep 12) wanted too much, which was his downfall. 

In Go, greedy moves can be very powerful, *if* you're able to defend your territory. However, a greedy move will also leave someone open to be attacked and can end up even costing the game.

Shu He wants it all - to be free of his royal duties, but also to be with Zi Ang, to find Huai Yi and live happily ever after. 

So, this line "Don't let me be defeated again" means sooooo much. Depending on the interpretation, it can be a plea, or even a warning. And obvioulsy a roundabout confession, but not just for love. 

It’s an admission that love, for Shu He, is a gamble, and he doesn’t want to lose. But sees that he likely will, and chances are stacked against him. 

But it’s also a plea for hope: maybe, love will not destroy him. Maybe Zi Ang will keep him safe, and he will be able to have it all. Too good to be true. Is it okay for him to open his heart like that?

Together, these two lines 

“我心甘情愿当这个替死鬼。”"I'm more than willing to be the scapegoat."

“别让我再输一次。”"Don't let me be defeated again"

form the emotional axis of their story.

Zi Ang’s line is the vow of sacrifice.

Shu He’s is the plea not to lose what that sacrifice has won.

And in the end, it is foreshadowing. 

Because Zi Ang will be the one to make Shu He suffer the most. And Shu He will lose everything – by Zi Ang’s hands. 

this respond to a post from @Boho - repeating myself a bit:

This scene is spellbinding and I think it has made it to BL history books. The in crescendo, the pace of all is perfection. ShuHe waiting for ZiAng with this feast after being tortured to ask him to leave. ZiAng knows is fake, showing him with his kiss that his love is real, his desire is visceral, but ShuHe hold onto until couldn't more. What it follows is devastating, yet is beautiful. The kissing is pure surrender. For me, the best scene in the whole series.