I've never used this card before, so I'm checking up on how to use it. The wording suggests that a demon goes to Tartaros when I discard it. So that means that only demons that I defeat go there and not ones that my opponent defeats, correct? Also, a demon that I discard with the demon discard LS's ability would got to Tartaros as well, yes?
Tartaros -
All demons that holder captures, discards, or has in Land of Bondage are placed in Tartaros. Release one demon to holder's territory from Tartaros when one of holder's demons wins in battle.
Lost Soul (demon discard) -
If a lone Hero begins a rescue attempt against you, you may discard one of your demons in your territory to shuffle this card back into owner's draw pile.