Your Best Friend (song)

"Your Best Friend" is the single by Japanese singer-songwriter Mai Kuraki. It was released on 19 October 2011 through Northern Music, as the third single from her tenth studio album Over the Rainbow. The song served as the theme song to the Japanese animated television series Case Closed.

Information
"Your Best Friend" is the 40th ending theme for Detective Conan. "Step by Step" is the official theme song for the Mie Prefecture-based Nemu no Sato Hotel and Resort.

Both songs were written and arranged by Kuraki and Giorgio "Giorgio 13" Cancemi from the R&B duo So' Fly. Cancemi, a Japanese-Italian, is also behind the song "Doshite Sukinandaro", a song by Cancemi's solo project Nerdhead (on Universal Music Japan label), which featured Kuraki on vocals.

Music video and radio airplay
This song was launched on Space Shower TV and bayfm Chiba two weeks before its official release.