Toshikazu Kawaguchi is a Japanese author, screenwriter, and director born in Osaka, Japan in 1971. He has worked across multiple creative mediums, including theater, film, and literature. Kawaguchi is best known for Before the Coffee Gets Cold, which achieved significant international success. The novel has been translated into 46 languages and has sold over six million copies worldwide. He also adapted the work for the stage, earning the Grand Prize of the Suginami Theatre Festival for this theatrical version. The novel version was nominated for the Bookseller's Award. Beyond Before the Coffee Gets Cold, Kawaguchi has been involved with the theatrical group Sonic Snail, for which he has produced, directed, and written. His creative works explore themes of love, loss, grief, and kindness.