The OVAs Nuku Nuku and Ryunosuke Nuku Nuku Nuku Nuku fighting the underwater robot Nuku Nuku Nuku Nuku   The TV series Nuku Nuku Opening Credits Nuku Nuku Opening Credits Nuku Nuku Nuku Nuku Opening Credits Nuku Nuku Nuku Nuku and Ryunosuke Opening Credits Ryunosuke and Kyusaku Natsume Nuku Nuku