Born in Japan, Koki started ballet at age 11 and trained at Tokyo Ballet School. In 2013, he moved to Switzerland to enter Rudra Béjart School, where he learned classical ballet, contemporary ballet, Martha Graham technique, acrobatics and theater. In 2015, Koki moved to New York City to join Gelsey Kirkland Ballet as a principal dancer. He danced principal and soloist roles in The Nutcracker, Harlequinade, La Vivandiere, and Walpurgis Night.
At Eugene Ballet, Koki danced several soloist roles inToni Pimble’s ballets including Monkey King in Mowgli–The Jungle Book Ballet, Cavalier in The Nutcracker, bridegroom in Peer Gynt, and Mercutio in Romeo and Juliet. He also danced in Suzanne Haag’s The Firebird, Val Caniparoli’s Tutto Eccetto Il Lavandino, and Stephan Mill’s Hamlet.