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...
She could also be trying to act like the 
perfect wife to put one over on me.
قد تكون تحاول أيضًا أن تبدو
.كزوجة مثاليّة لتخدعني أكثر
Vielleicht will ja sie die perfekte Ehefrau
spielen, um mich zu täuschen.
C’est peut-être pour me duper
qu’elle veut devenir l’épouse idéale.
Forse vuole recitare la parte 
della moglie perfetta per ingannare me.
Pode ser que ela esteja tentando agir
como a esposa perfeita para me enganar.
Возможно, она хочет казаться идеальной,
чтобы в дальнейшем обмануть меня!