I wanted to ask a question in the Shirou's servant thread, but the question involved Sakura instead of Shirou, so here goes.
What if Isaac from The Binding of Isaac was Sakura's servant? For those of you who don't know, Isaac is a traumatized child who escaped into his mother's basement because she went mad and heard the voice of God telling her to kill her son. There, he found a horde of monsters that tried to kill him, and he defended himself by...crying at them. Yeah, BoI isn't a happy game. For ideas on how he would work as a servant, you can read this:
http://bindingofisaac.wikia.com/wiki..._of_Isaac_Wiki
I imagine he would bond well with Sakura, considering their shared tragedy.