Uoron was trying to tell Reen that she should open her heart to him and let them start their "something" together.
While for Reen, what she was trying to convey was that she didn't want to start any "something" as she was already contented with what they have now and didn't want to risk whatever they may have now of turning into "nothing".
Even if they do get together it could still lead to them separating and both will end up with "nothing" so she rather not risk it.
Her dilemma that she did want him to be inflicted more than necessary with her own problems as she already involved too many people for her selfish desires for revenge also stopped her from pursuing whatever "something" they could have.
"But if that's the case, isn't it that your setting yourself in a box. How will you learn and grow if you always think that you'll end up missing everything and not try to gamble about the risk of having that everything? You just need to fight for it so that it won't go back to nothing if you really wanted to." He said after a few minutes of silence.
"Yes, I agree that to be true… if I don't try to fight for that anything I'll never get that something and it will forever be nothing… But I rather keep that little something than risk the possibility of it becoming into nothing. That something can then eventually grow and became my everything…" She said in a small voice
"What you meant was, you didn't want to risk whatever we can have because we will end up separating in the end so you'd rather keep the memory and feelings you have to yourself isn't that it?!" He mentally thought as his eyebrows scrunched up in anger at the stubborn woman.
Reen finally admitted to herself that she does like Uoron, not in the same way that she liked Sae but something deeper. However, she did not have the time to deal with anything else as she wanted to deal with her past first to enable herself to finally move forward.
If after everything and she emerges alive after the mission then she can deal with whatever the future may hold then.
Reen was staking her everything in this mission, whether or not she survives especially with her unexplainable illness did not matter. Her priority as of the moment was to kill the wicked witch, everything else even her own life and death only comes second.
Uoron also knows that he loves Reen deeply and as cheesy at it may sound she was even his first love. He knows base on her stubbornness and believes that as long as she could achieve her goal even if at the expense of her life she would grab and finish this to the end.
He wanted to bring up his feelings even if in a subtle way not only because he wanted her to know about it but also thinking that he could use it to stop her and hold her back from her recklessness when the time comes but he underestimated the strong conviction she had.
Both could only silently sigh to themselves. Seeing that the topic seems to have gone way out of their initial one and knowing that both parties are not willing to back down on their beliefs, the once heavy and serious surrounding turned into a soft and warm one.
Reen could not help but laugh while Uoron softly chuckled at their currently weird situation.