In order to prove to Yuri that they are actually a married couple, Loid and Yor are supposed to kiss. Loid is willing to get this done immediately for the sake of Operation Strix, but Yor can't do this sober, so she ends up downing a bunch of wine and gets drunk.  Yuri sees his sister this way, also gets drunk, and is unable to make rational decisions anymore...
Next time, I'll prove that 
you're tricking my sister!
!وفي المرّة القادمة، سأثبت أنّك تخدع أختي
Nächstes Mal werde ich beweisen,
was du für ein Playboy bist!
¡La próxima vez tendré pruebas
de que engañas a mi hermana!
¡La próxima vez tendré pruebas
de que engañas a mi hermana!
Et je prouverai que tu utilises ma sœur
pour arriver à tes fins.
La prossima volta troverò le prove 
che stai raggirando mia sorella!
Ainda vou provar que você
está enganando minha irmã!
В следующий раз я найду доказательства,
что ты подло обманываешь сестру!