So rather than Hayan being a trap I think her not getting periods is because her body can't handle giving up blood every month for a week, as we saw in previous chapters they don't get much of any food at all. Remember Hayan has been stuck their for much longer than Jinyoo and we don't what Gyuh- Wool feed her or if she even got regular meals. So Hayan not getting her period is probably because her body lacks substance. If gradually you start eating less and less until you're eating next to nothing you'll stop getting periods because you're body can no longer produce enough blood for you to get a period. So yeah, and I do think Hayan is a trap just not the gender kind.
So rather than Hayan being a trap I think her not getting periods is because her body can't handle giving up blood every month for a week, as we saw in previous chapters they don't get much of any food at all. Remember Hayan has been stuck their for much longer than Jinyoo and we don't what Gyuh- Wool feed her or if she even got regular meals. So Hayan not getting her period is probably because her body lacks substance. If gradually you start eating less and less until you're eating next to nothing you'll stop getting periods because you're body can no longer produce enough blood for you to get a period. So yeah, and I do think Hayan is a trap just not the gender kind.