1-(Hatsujou) - Younger bro Takao found his lifetime pair, the teacher Yuuki.
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2- (Yokujou )-[Spin-Off] – Big bro Hayato’s fated pair, Shirou turns out to be a rival yakuza.
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3-(Misujou)- [Sequel of 2] - Hayato somehow turns into 'Eve' type then bears lovely twins!
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4-(Shikijo)-[sequel of Yokujou & Misujou]
Hatsujou