"I'll let you meet Shiro. I promise!" Jin the cat promised Mugi, who was grieving over the loss of his beloved dog Shiro. Jin loves Mugi very much, and after hearing the story of the Rainbow Bridge from his owner Kageyama, he decided to let Mugi meet Shiro at the end of the rainbow! Will Jin be able to save Mugi from her sadness? He invites the pigeons and squirrels from the neighborhood, and now Jin's big plan begins!