Damn It I Asked for a Gundam!
This is the video for the Ichirou Mizuki song It Is Not This! Korejanai Robo! which tells the heartbreaking tale of a child otaku who years from a Gundam toy but whose clueless parents get him a cheap bootleg instead. Of course our little hero isn’t going to take this slight, so he takes his revenge on the wannabe Gundam. But this mecha knockoff has a few tricks up his sleeve.
Found via super fangurl Ardith Carlton.