I think the gems are part of his soul and you’re only able to get them once the person is dead because in earlier chapters there was a big gem and the king said it was ml’s mother? Idk I could be wrong tho :<
Plus if you think about it he couldn’t show it either because of the potential repercussions from his actual wife. I mean if you consider how it’s gone this time around compared to the last. She has been in much more danger because he has shown affection for her.
As they should ???