So, all of Reiko powers and strength are based in what people thinks about Revendia-Sama (Jaryuu) and the legends about him, she's the real "Revendia" due to this.
Revendia is said to be able to devour stars, as the legend says he ate a Sun (chapter 150), she should be Star level.
And to further enhance this, her headcanon powers made up a new ability that further enhanced her capacity.
For some reason, hearing the Legend about Revendia eating the Sun made her mind think that Revendia also brought the Gravity to Earth (chapter 152)
And in FACT, she actually used the Technique that her mind made up (chapter 152), yes, she used the power that Revendia used to bring gravity to the earth and rotate stars because her headcanon believed Revendia COULD do this
Btw, Reiko current is rated as Class 10 lifting strength cuz she can carry a giant elephant with a single hand as we can see in her profile, however, later on in the novel, all of her strength was multiplied by 343.2 milion times cuz Revendia said she could power up (chapter 186), yeah.
I don't really know how high is Class 10 multiplied by 343.2 million times, but i think there should be a way to calc it tho.
Also, this also means her Star level strength was multiplied by 343.2 million times too, I dunno how strong is this tho, how can we calc this?