^Interesting thought, Elaedan ^^
Okay, last thing for now...
In the first/second chapter, when Mephisto tells Rin to change in the limo he remarks on the tie, saying that he 'knows how to tie it well.' His face as he says it seems like a legitimate jab at the fact that Rin only now learned how to tie a necktie properly after Fujimoto's death. And then I wondered, wait, Mephy wasn't anywhere in that scene (they are in the church courtyard when Shiro ties the necktie for Rin), so why does he remark with such finality/sureness?
Either a) he had some sort of familiar or something that let's him see what was going on w/ the church/twins (I doubt he'd expose himself to the twins physically at any time-- Rin had no idea who he was) or b) Shiro called him after Rin's first incident w/ the 'coal tar' (the scene where he blows it away thinking it was a bug)
I lean towards option a mostly because it seems as if Shiro rarely called Mephy-- for whatever reason. Also, did anyone inform Mephisto on how Shiro died? I mean he seemed perfectly alright at the graveyard and I'm pretty sure a Gehenna gate opening is a big deal. I guess Yukio told him eventually, but still... no reaction at the grave. As if he knew about it already. Demon or not, Shiro and Mephisto were friends; not showing any outward emotion would be difficult, unless he mourned right at the time Shiro died.
I dunno, what do you guys think? Do you think Mephy planted something at the church to keep up w/ the twins?