I'm currently playing an MMO where on top of HP damage, you can get Minor Injuries or Severe Injuries (usually from dungeon traps) and they will deplete you HP a little at a time (like 2 points every 5 minutes) unless they are healed. You can heal them either by standing in a heal spot for 3 minutes (per minor injury, longer for severe) or by using these "Injury Kits" that are actually kinda expensive.

It could be something similar with Sapphira?