Why is Midoriya called Deku? Since the start of this series, we have seen Bakugou call Midoriya Deku on countless occasions. As a part of a bad relationship stemming from their childhood, Bakugou mockingly calls Midoriya “Deku”. The reason he calls him that name specifically is that In Japanese, the name of Midoriya Izuku is written as 緑谷 出 久.