It's Yuji's elder sister

Tama onee-chan

Oh my, who might you be?

Konomi

Wah, wah, that's wrong~...

Ah

Ah

Takaaki-kun is always looking after me.

Ah, you must be Takaaki-kun's big sister?

Big sister?

Really? はい？

"onee-san"... お姉さん…

Wow, you really grew up, eh? I told you that you would♪ まってねー 「どかーん」ってなってか でも私はゼンゼン予定 って言ってあげたの

She's his... big sister? 姉さんは… いってる？