yukiyuzen said: Its a typesetting decision. They don't actually say "I".
Either it's a translation issue, since the translation also had pronouns, or it's intentional by the author to point out that this yukkuri is different. The typesetter is not to blame for this one.
It's a translation decision (not mine, though). In my opinion "I" is acceptable occasionally when sentence structure calls for it, and when the yu in question is smart.
(Japanese omits a lot of pronouns, so adding names and translating everything to "Marisa this, Marisa that" can produce very clumsy sentences sometimes).