The historical Buddha, Shakyamuni, says in the Pali Canon that when all his teachings have been lost, another buddha will appear on earth and his name will be Maitreya ("Miroku" in Japanese). Thus Miroku is often seen as a kind of saviour, who currently resides in one of the Buddhist heavenly realms. There are famous statues of Miroku at Koryuji Temple (Kyoto), Chuguji Temple (Nara) and Yachuji Temple (Osaka).
Miroku Bosatsu at Yachuji Temple.
Miroku Bosatsu at Koryuji Temple.