They don't use protection. In fact they want the second child.
They didn't use protection after finding out that Hyesung could no longer bear a child but it seems that the magical herbal tea has rejuvenated his uterus to be able to bear another little rascal lol
I remember a doctor in the story mentioned that it was a miracle that Hyesung got pregnant since he was a recessive omega and it was hard for them to have the second child. Since then, they don't use the protection
ik but they 1st got a child and that was hell for hyesung, then dojin got him knotted by accident, and i thought that after those 2 incidents they'll start using protection Σ( ￣□￣||)
the bitch at the last panel looks like your uncle byul, don't go doki doki for him yet
also, i truly thought hyesung and dojin were using protection, HAVEN'T THEY LEARNED NOTHING????
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