[Rei does the same to the other shower, and when Usagi pops back out, she's ready with an answer.]

Archer's a friend and an ally. And it's not Archer-san, just Archer. He'll refuse any title you try and give him, and any thanks. [Lips quirked, she runs a finger along her cheek, trying to think of the best way to explain...]

He's not human. He's a spirit, from a different time and place. He's honorable to a fault, but not terribly open and friendly. I just did him a favor, and he repays me by taking care of the cooking. It's one of the few things he enjoys doing.