On the December 6, 2009, Kusumi Koharu graduated from Morning Musume and Hello! Project at the Morning Musume Concert Tour 2009 ~Nine Smile~ concert at Tokyo Welfare Pension Hall.

There was a change to the setlist for the final day of the concert tour where Rainbow Pink, one of Morning Musume’s songs on their album Rainbow 7 album performed by Sayu and Koha (under the group name Shigepink and Kohapink).

According to fan reports the graduation ceremony started after Resonant Blue (which is the last song on the setlist, not counting the encore songs). The members all read their farewell messages in order of generation: Aichan, Gaki-san, Eri, Sayu, Reina, Aika, Jun Jun and Lin Lin (all of the members crying during the ceremony) and then Koharu reading her final message to the group and to the fans.

Koharu during the graduation ceremony

Here are the speeches and some more information about the final moments of Koharu as a Musume, this is the full version from the concert rip (full translation credit: Turbos86, from THIS article at H!O, special thanks to Kuno):

Translation of the graduation ceremony (full)

After Rainbow Pink, the audience does a 3 minute Koharu Chant.
Koharu runs back on to the stage.
Koharu: Thank you everyone!!! Wow!!! It’s completely red! (Glow sticks) Thank you. Thank you very much for the warm Koharu call!
Thank you! Everyone in the 2nd floor, thank you too!
I, Kusumi Koharu, on today, Decemeber 6th would be graduating from Morning Musume and Hello! Project…will graduate.
Everyone who has supported Kusumi Koharu of Morning Musume, I thank you from the depth of my heart!

(Never forget, instrumental versions begins playing in the background)

> Takahashi Ai’s message Niigaki Risa’s message Kamei Eri’s message Michishige Sayumi’s message Tanaka Reina’s message Mitsui Aika’s message LinLin’s message JunJun’s message Koharu face the audience and reads a prepared message Final MC Fans does another Koharu chant Fans does Koharu chant again <

(Concert ending announcement is played.)

Fans ignores the announcement and continues to chant Koharu’s name.
After 5 minutes, Koharu reappears on stage.

Without a mic, Koharu yells into the audience:
(Waving her arm non-stop)

information found at: Hello!SayuNii