Episode 43...

Before Ishid left Scarlet that night, he said something to her.

"I'll do something to make it possible for me to stay by your side. So, whatever happens, just trust me."

His words echoed inside her head, over and over again, and it occupied her thoughts like a broken record on repeat as she looked outside the carriage window. 

She didn't understand what he was talking about, for him to do something that'll make it possible for him to stay by her side. Only the members of the order are allowed to be near her in extended periods of time. The palace servants, even though they serve her, aren't allowed to be 15 paces near her.

Of course, knowing the difficulty of the challenge, Scarlet knew Ishid had a plan. She just didn't know what it was, since he was tight lipped about it. But she decided to trust him anyway, and wait.