User blog comment:B214/Shin DxD 1 discussion/@comment-78.4.96.213-20180721163242/@comment-203.215.116.107-20180721235613

Vanishing welsh, tell me how many mixblood angels and reincarnated angeld are there compared with mixblood and reincarnated devils. There's your answer.

Sacred Gears are originally created for human use. It's just that devils had interacted with humans far more many times compared with angels. Not to mention the reincarnation system is the devils' original invention.