Neither is 'planned' to be toxic. Both Lotar and Mal are evil in alignment, but that hardly makes them toxic in a relationship with MC. The characters as we see them, especially in the demo, aren't all that there is to them, nor will they stay stagnant - as there is progress, there's always development. Now, can you, as the reader, find their actions undesirable and toxic despite my own attempts at portraying them otherwise, sure, there are as many points of view as there are people (plus there are 5 ROs, so it's more than easy to skip the ones you don't want to experience), but just because the setting is dark, doesn't mean every aspect of the story has to be the same.