Ok, so read this:

The two partners in a strong pale relationship will serve to balance and complement each other’s emotional profiles, and thus allow their other relationships to be more successful. 

It’s often ambiguous especially among young trolls whether a bond formed between an acquaintance is true moirallegence, or the usual variety of platonic involvement. Furthermore, romantic intentions of a more flushed nature can often be mistaken for paler leanings, much to the frustration of the suitor. 

This kind of relationship may be most similar to the Greek concept of στοργή, or “like family”, which can be defined as "a desire to ensure the well-being of another."

While the definition of Moirallegiance usually aplies better to cases in which on of the trolls is dangerous and the other is strong enough to calm them down, there’s always an emotional factor:

It is a form of guardianship, but it isn’t simply about being platonic soul bros forever. They are a protector of their moirail’s heart. They keep each other grounded.

Humans don’t really need to keep each other grounded for a social purpose, such as avoid violence against others. BUT. We do need to keep each other from hurting ourselves, being physically or emotionally. Pay attention to the conversation between John and Roxy:

Roxy is being extremely pessimistic and depressive here, due to everything that’s happened. John is trying to take the role of the optimistic friend, because he’s concerned about her. He’s trying to give her hope, something to fight for, something to LIVE for. He’s trying to keep her emotions in line so that she can overcome the situation and, at least, live what’s left for her with a better resolution.

And I think what he’s doing might be seen as a moirail’s job.

Now, there’s Terezi:

She didn’t actually made Roxygen canon… we have seen their painfully evident romantic tension before. The point is, this time is different because she’s not seeing it as a simple human like us, but as a troll:

Despite the platonic appearance of this role (as we currently understand it) to us humans, trolls consider it a type of romance.

Also, there is the hug thing. 

She could have said HOW 4BOUT 4 K1SS, but she didn’t. Kisses are for matesprits and kismesis. The way I see it and if I remember correctly (from Gamzee and Karkat’s pale interactions, mostly), a hug is something normally performed between palemates, much like shoosh paps and feelings jams, right?

So, basically, I think Terezi was talking about pale romantic tension more than flushed, and that’s valid. Or maybe she was indeed talking about a possible matespritship, who knows? But hey! Either way, it was Roxygen! And I guess, pale or flushed, it’s enough to satisfy our hunger for romance for the moment.