This story had a lot of potential and so many viewers have already stated that it was good as in japanese drama and manga version, I totally agree with that though I haven't watched those version. As in the movie format, the entire plot looked a bit turbulent , rushed and unfinished, the dots are not connected properly, events seems missing and with all this chaos going,this movie left with no spirit.
I can't comment of Kimi wa petto as I never read or watched it .. but I know in drama format this plot is still workable ..but in movie format ..NOPE ...

Everything is so confusing that It actually made no much sense . Totally ridiculous