Yu boy touches his cock with single-minded devotion...
Yu: Oh... I'll get it again...
Tamae:Yu, what are you doing in Mom and Dad's room? Ah! You're playing with your dick again!
Yu: Wow!! (launching!)
Yu: Because... because... Mom told me to work out!
Tamae: What? What does that mean? Tell me in detail!
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Tamae is 12 years old in earth age.
In a complicated family environment under her care, her younger brother teaches her.