Watanabe 10 years old Shiraishi - 2 years old
Watanabe is 20 years old and Shiraishi is 8 years old.
Watanabe is 30 years old and Shiraishi is 18 years old.
Watanabe is 40 years old and Shiraishi is 28 years old.
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Ten years, ten years, reincarnation
Who knows who's intention, where it starts and ends