If you loved Groper Train: Search for the Black Pearl, try Sexy Timetrip Ninjas
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
What they share
Both films are directed by Yojiro Takita, and they both carry the 3am cult, sexy mood tags, and they sit in Comedy territory. If that's the register that drew you to Groper Train: Search for the Black Pearl, the second film will land in a comparable space — through a different lens.
3am cultsexy
What Sexy Timetrip Ninjas is
One imagines this film was exactly what it sounds like. A ninja is tasked with finding a treasure to restore his clan, but a rival ninja stands in his way, until they are both warped to 1984 Tokyo. It probably played better in Japan.

