User blog comment:Xilinoc/Ch. 630 - The Twinned Twilight/@comment-24726378-20150611162918/@comment-24726378-20150612044225

I guess in a way, the twins also had a tragic past. (Forgot about them) like you said, they never had their own identity, even at birth, they were confused for each other. Yhwach's power was always to "fix" ailments of others, so like demotivator said, the schrifts are basically his way of fixing their trauma and mental scars.