Because her breasts are too big, she can't play the keyboard Harmonika! Her sister's huge breasts are obvious at a glance! No condom in a short-sleeved sailor uniform! J-cup, 109cm. (Rin CHRV-210)

The younger sister is practicing playing the Harmonica keyboard. Because her breasts are so big, she probably can't see the keyboard. Indeed, she said she almost tripped on the stairs because her breasts were blocking her view… This is a common problem for busty girls. But, whenever she encounters trouble, she can always ask her brother for help! After all, we're siblings! While this is considered a form of repayment, could she also ask her brother for advice? Okay, how about she makes her brother feel good with those proud breasts?