Does damage calculation mean you lose life points for example does the owner of Spirit Reaper when an monster attacks it in defense position?

In the scenario mentioned, where Spirit Reaper is attacked by a monster in defense position, the owner of Spirit Reaper does not lose life points from a damage calculation. Defense position monsters do not inflict battle damage, so even though the attacking monster's attack points exceed Spirit Reaper's defense points, no damage is dealt to the player's life points.