Borrowed Vitality

Your touch carries a power both wondrous and terrible. When you mend another's wounds, you draw their suffering into yourself. Every life you heal diminishes your own—a burden you bear willingly, though it costs you dearly. Whenever you restore hit points to another creature (through spells, abilities, features, skills, etc.), you lose hit points equal to the amount restored. You cannot reduce yourself below 1 HP this way.