Is this a bug with flame loss?

I didn't see anywhere that you lost more than 7 flame per hero death, but it might be different in this fight? I'm not sure, I couldn't find it anywhere. Also lost a random amount of flame a few times for no reason. I went from 46-19 for 1 death then 19-0 with 1 hero still up. Is there a bug with the +1 hero relic where the game thinks you run out of heroes? This was during a Pacifist run.