Ai, Sunakawa's sister three years his senior, is shocked to learn during a home visit that Takeo is dating. Having secretly harbored feelings of her own for Takeo, Ai is suspicious of Takeo's girlfriend and launches her own investigation...
Maybe she's two-timing 
him or having an affair.
...ربما تخدعه أو في علاقة مع شخصٍ آخر
Vielleicht hat sie eine oder zwei Affären …
Puede que lo esté engañando 
o esté teniendo una aventura.
Puede que le esté engañando 
o esté teniendo una aventura.
Je ne sais pas 
si c’est parce qu’elle le trompe,
Forse fa il doppio gioco, o lo tradisce.
Talvez tenha um outro
 namorado ou tenha um caso.