Paula and Sylvie were growing up in strength, mostly thanks to Reigner and his identity. The weapons he provided for them were also useful in the creation, and unfathomable creations were likewise born out from it.
Their contribution was not as high as they genuinely wanted, though.
It was because another world's experience was just too good for them, but it was, at some point, bound to change. Of course, it was the perfect time to fight with the death on the line.
As to why Paula and Sylvie thought like that, it was because Ho Chen truly was the strong opponent.
"You two are his women, right? Haaa~~ This world is truly regressing!"
She could see the reaction of these two ladies during her small exchange with Reigner. It was minuscule and barely seen, but all three ladies here were already old enough to spot these, even more, when one was truly 'liking' to tease and charm.