Can’t believe I never answered on this topic!
For me, I’d say there were quite a few video games that “stirred the pot” for my fascination of zako.
I’d say, I was always interested in the henchmen concept from the early days of playing Goldeneye on N64, mowing down the soldiers (which seemed with the shitty graphics to be wearing tight pants, which ties in with a seperate spandex kink of mine, but that’s a different topic for a different day). And even before that, I really liked the uniforms of revolutionary war soldiers, where a lot of the old artwork shows their white uniform pants as tight almost spandex-like riding pants, and kind of sub-imagined those soldiers getting mowed down in those tight uniforms.
In terms of the female aspect, I’d say it was first “nudged” by watching Gundam Wing. I always liked Oz soldiers and officers because of their uniform style being very colonial-like, much like those same revolutionary war soldiers. Seeing characters like Noin in those tight riding pants was so hot and even crushed on Hilde for being her cutie self. Though not one for explosions, I still loved one particular scene where there was a nameless female Oz soldier that was in a command station working as an officer that was communicating with a lot of the mobile suits, but then Heero ruthlessly kills her and everyone at the station by slicing through it with the laser sword and blowing it up. I’m not a fan of the explosion, but the concept that this nameless female Oz soldier died in battle definitely stuck with me subconsciously.
Then, came along Perfect Dark. That was probably the first main thing that really got me interested and invested in female zako as well as eliminating them, with the female dataDyne guards. Of course, it was mainly driven by (once again) the tight white pants they wore, but having to eliminate them physically in the game I think was a huge part of me really becoming interested in killing female zako. Not to mention, my other fantasy is pants wetting/soiling out of fear, and the fact these guards could be disarmed and forced to surrender was especially hot!
Around this same time in 2000-2001, there were many other video games starting to incorporate enemy henchwomen. I’d say following my captivation with Perfect Dark, I’d watch my cousin play two games - first was Diablo II, and one specific part of the game I remember was when he was exploring some old castle, the place was littered with dead Rogues or some other female soldier of some sort. That stuck out with me VERY clearly, and I’ll never forget thinking about that concept of discovering a room full of dead nameless girl fighters. I still remember vividly there was I believe one or multiple dead rogues lying dead at the dinner table, as if interrupted in the middle of a feast, which certainly stuck out to me as well.
The second video game I watched him play was Return to Castle Wolfenstein, which I’m sure a lot of people here know about the female elite guards. I remember being in love with the tightness of their uniforms, and thinking about them dying as my cousin struggled to fight them cause they were pretty hard for the casual gamer.
That 2000-2001 era was such a good time period for zako in my opinion. There were two more games that followed the trend of female henchwomen and I absolutely adore. The first was Final Fantasy IX, with the Alexandrian Soldiers. I LOVED that their uniform was a one piece leotard, and was even more excited to fight them in battle. I only wish that the big scene where Kuja wipes out the Alexandrian fleet would’ve showed the soldiers actually dying or showed their dead bodies floating in the water or washing up ashore, rather than seeing them run off screen right before the ship explodes. I mean, I’d assume everyone died being that Queen Brahne still died despite having an escape pod that somehow made it to shore, while all of the girls and mages were essentially still trapped out at sea either dying in the explosions or eventually by drowning for being stranded out there. Kinda spins my gears for a fanfic now that I think about it LOL.
The other game I think about in this era was Half Life. Though I wasn’t a fan of their super-fast movements in terms of trying to kill them, I still very much loved the female black ops assassins. The thought that highly trained female assassins being sent in by the government to cover up a conspiracy is hot, in addition to the fact they LOOKED HOT with their tight spandex catsuits and tactical gear. I love how when they would be killed, their goggles would go up by their head to show their lifeless eyes that were actually still made up with eyeliner and shadow, still very much feminine despite being such cold blooded killers, willing to kill anyone and everyone innocent and defenseless as part of their missions.
Of course there would be many games and movies that would fill in this genre, but I’d say those five video games and one anime series that really set the foundations for what I love about zako today, especially with the fact they all literally hit right at the same time, perfect timing for me as my hormones were starting to shape in that same year to year and a half period.