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...
Er, no. I was just admiring 
what lovely siblings you are.
عفوًا، لا. كنتُ فقط أبدي إعجابي
.بكم أنّكما شقيقين رائعين
Nein, ich dachte mir nur:
Zwei Geschwister wie Pech und Schwefel.
Ah, no. Solo pensé que son
unos hermanos estupendos.
Ah, no. Solo he pensado
que sois unos hermanos estupendos.
Ah, non…
Je vous trouve juste vraiment soudés.
Oh, no.
Não. Só estava admirando
dois irmãos adoráveis.
Ой, нет.