This is quite a twist I don't expect will work.
I mean, what is the dirty technique? Is it even dirty? It's about "merchandise"!
But for a merch to work out, you have to make a deep impression by the movie. Sometimes a movie doesn't ring as successful because the bad managing of merch (or lack of funds) and while it might be good review, people might forget it soon because lack of merch as a reminder.
Umeki being a hinged weirdo as a film maker is understandable, and I'm glad he's dedicated enough (and not a plain sexual offender) to a movie. Even a tad idealistic, even. At this point, Fuyumine winning is just the matter of story having to go on, and Umeki despite being cunning, is actually giving a good fight.