The Countess' Situation

Rex initially thought the Countess was exposed to Chaos energy—when the Fifthborn teleported him into the realm of chaos, but he remembered, that the Countess quickly teleported him out of there so the exposure shouldn't be severe.

It was mere seconds, and the Countess shouldn't be corrupted because of that.

He would be damned to think that the Countess is that weak.

No matter how powerful the chaos realm was, the Countess was a literal Goddess. 

However, minutes later, Rex was exposed to the realm of chaos again.

A reckless move from him as he saw his best friend, Edward, dissolve into Chaos energy.

Out of shock and desperation—Rex insisted the Countess open a portal back into the chaos realm. She already warned him against doing that, especially, since her divine energy was in low reserve after breaking the First Breath's limiter.

But Rex doesn't listen and demands her stubbornly which she eventually complies with.