Oh boy, you could say that Kaiba was NOT prepared for that question when it came to Yugi asking about last night. Especially when the topic was going to include telling him about Dartz. How was he going to explain about Dartz when he was already unhappy about the former king being here anyway. 

Well, it was time for the cat to be out of the bag. With a heavy sigh as he sat on his rear, Seto crossed his arms like he was annoyed (which was slightly true). "Yami brought Dartz with him here. Apparently Dartz is no longer as he was and is even being accompanied by Timeaus. Also. Mako is here. He was being stalked by Apep's followers." He explains plainly. Not explaining yet how he's actually the blessed of Set. 

Surprised by Ishizu's appearance, she was startled a moment but smiled. "I slept well, thank you ma'am. And yourself?"