So here's an obscure tokusatsu series that had quite a bit of GiD scenes in its second half and in the last episode there is finally a DiD! Episode 24 technically had one, but there was no good shot of it and it resulted in the villainess getting a bad end. Anyway, the main villain, Dagger, manages to catch Rosemary, the mom of the main hero.... and himself. Yes, the last episode revealed they're both twins. This came out a year before The Empire Strikes Back, you think this may have influenced George Lucas a tinsy bit?

Anyway, she is tied via chains to a chair and gagged with a muzzle starting somewhere around the 8:30 mark. Very odd for a series to have multiple main protagonists killed off and none of them being the MC's parents.
https://www.dailymotion.com/playlist/x6p1kr
You also don't really make it out until near the end, but Dagger apparently has a hectogram tattoo on his left cheek. What did Toho mean by this?