@KYOUSAYA4LIFE As pointed out, that's "Ittadakimasu". "Ittekimasu" is "I'm going out", and "Itterasshai" is something like "Come back safely". They're using it correctly.
MOVIE 4 HURRY THE GOD DAMN UPPPPPPPPPPPP DO YOU KNOW HOW LONG IVE BEEN WAITING WELL SORRY WE VE BEEN WAITING HOLY DAMNNNNNNNNNNNNNNN HURRY UPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
I thought I recognized the art style. Then I realized this was by the artist that left Pixiv because people wouldn't stop posting their work on other sites.