"ENOUGH! ENOUGH! I FORFEIT!" Sei shouted as the metal barrier cracked to see that Sei was hiding in a water bubble that had been formed only recently with literal foam and bubbles coming out from the big bubble itself. (It's a bubble on fire!!)
From the difference in temperature inside and outside of the said water barrier, the water bubble looked as if it was not able to maintain its shape. Sei was merely inside there because of the extensive wounds she had suffered. Muscles and bones were exposed from the burns and when she talked, it looked like her muscles were doing the talking.
Her eyes were also gone from the extreme heat that came from the explosion but the fact that her body remained intact despite everything else means that she was still able to hold against Pepper's explosions if Sei had fought Peppers at full strength at least half a year ago.
Taking indefinite hiatus, rewrite chaps and post at times. tyvm