Your character's life points (LP) are a secondary hit point total that is only exposed while your character is Dying. If your life points are reduced to zero, your character dies.
Characters of the same level always have the same maximum amount of life points regardless of ability scores. A character's maximum LP is 10 at level 0, plus 5 for every level gained.
Monsters and other animalistic creatures do not have life points, instead dying permanently whenever their hit points are reduced to zero.