Mokuba looks at Yuugi owlishly after he tried to explain away Seto's behavior. His expression read as only one word, which he vocalized with such disbelief and smarm that he definitely earns his place as a Kaiba.

"Really...so you 'had him drink some of your blood' after he broke through his bedroom window, and your apartment window? That was totally voluntary, and not at all under any kind of duress?"

Listen, Yuugi. He likes you. You're a good guy, perhaps too good for the likes of your situation! But that was such egregious bullshit that even though Yuugi does look better, Mokuba absolutely can't believe the words coming out of his mouth.

"And while we're at it--you mean to tell me that you guys were just talking reeeally close to each other just now?"

Oh no, oh no, the arms are crossing! Yuugi now you fucked up.