I just now got around to reading the manga adaptation of Trusty Bell: Chopin no Yume (a.k.a. Eternal Sonata) by Kuroi Mimei and I've got to say—I'm a little weirded out.
For one thing, a huge chunk of the cast is missing from the 10-chapter story—including my favourite unbalanced character, Viola. Also, the plot has been hacked down and rearranged, but that I don't mind because Japanese role-playing game plots often need a lot of paring down. And for some reason, Chopin looks more like the real-life Chopin than he does like the video game Chopin despite the mega-huge pocket watch.
The manga completed its run under Dengeki Comics last year. Kuroi has drawn two other manga that I know of: Kimikiss—Lyrical Contact and D.C. the Origin.
Check it out for yourself without spending a dime. You may as well since there likely aren't any plans to bring it Stateside.
Trusty Bell — Chopin no Yume [One Manga]