According to Wikipedia, Kyūkyoku!! Hentai Kamen ("Ultimate!! Pervert Mask") is a comedy manga series that tells the tale of a young martial artist who transforms into a bizarre hero of justice by wearing a pair of panties on his head. The manga was published in Weekly Shōnen Jump between 1992 to 1993 then adapted into a live action film in 2013.
Kyōsuke Shikijō is a high school student skilled in kenpō, but incompetent with girls to the point that his interaction with them gets him into painful situations. One day he saves a girl named Aiko Himeno from bullies and is immediately smitten with her. When she is taken hostage by a group of criminals during a bank robbery, Kyōsuke is forced to take a disguise to save her without being recognized by the crooks after an earlier incident where he reveals himself on a megaphone. When he accidentally puts a pair of panties over his head instead of a normal mask he undergoes a transformation: due to the perverted genetics of his mother (a S&M worker), he is able to awaken the full potential of his body. Running out wearing nothing but the panties on his head and underpants covering his loins, Kyōsuke, now christening his masked self Hentai Kamen, uses his power and perversion to defeat the criminals and save Aiko.
Full movie here
