Responses
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Ryou is 2 years older than Ayato
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well, in general people usually start to gain childhood memories starting from 3 years old. Some others who can remember things that happen from 3 years younger can be considered as smart or even genius kids. Those children could be extremely talented in certain things.
I don't get why the summary above and on the back cover of the manga says they were childhood friends when they were 2 years old. They look older and parents don't usually leave 2 year olds unattended. Besides can any of you remember anything from when you were 2 years old?