Thinking of the 1st battle between her father, Red Hulk, and Thor in Loeb's run. Rulk had the ability to absorb energy of myriad types, including gamma, sound, and, apparently, Asgardian magic.
Thor commented on Rulk's inability to absorb non-gamma energy at a later date and rematch, if memory serves.
Presumably the fight was as favorable to Thor as it was the 2nd time BECAUSE Rulk could no longer do that.
Betty has demonstrated the ability to drain energy from opponents, too.
She did so to Rulk himself to reveal him as General Thunderbolt Ross, for instance.
Presumably, SHE, being so like her father in terms of powerset, possesses the ability to absorb energy from Kurse in that same way, making herself ever stronger and Kurse weaker.
Unlike her father, nothing (to my knowledge) has happened to Betty to take this ability away.
If so, the battle lasts only a short time beyond the point where Betty decides to do this to Kurse, and proportionate to how much she really wants this fight ended.
She also did so in the "Heart of the Monster" (HoTM) storyline by Greg Pak, along with her husband, absorbing the gamma energy that would have wasted a city without her interference. The pair grew so enormous as a result that they were able to stomp the behemoth dragon, Fin Fang Foom, as if he were no more than a housecat.
Same way it helped her father against Thor, I imagine.
Take a look at how easily Red Hulk disposed of Thor when Rulk still had HIS own energy-absorption ability, in the scans by Bada near the bottom of the following page:
There was actually a small discussion on this in another thread I was involved in. I thought it was just a case of Rulk exploiting the same loophole Iron Man used to control Mjolnir 30 years earlier:
If there's no ground to determine direction, no ground to pick Mjolnir up FROM, what does it mean to have a "no lift" enchantment. You need a ground to define "lift", right?
Then someone pointed out that Rulk seems to have absorbed something beyond that. Why is Mjolnir, sole property of Thor, producing LIGHTNING when Rulk swings it at Thor otherwise, as it is only supposed to do for Thunder Man himself?
Red She Hulk absorbing energy from Kurse should theoretically result in the same outcome as Rogue versus Thor, Round 1 (see Avengers Annual #10, 1981) or Rulk versus Thor, Round 1 (see, again, Badabing's scans in the Rulk Respect Thread).