There is an old movie with a lot of sex scenes and some zako stuff, which you may like.
Three prostitutes and one man blackmailing a millionaire. One prostitute can be seen with a gun, and another one will help questioning a hero, so they're kind of bad girls with no skills. Two prostitutes will be killed off-screen, and we will see only one of them dead. The most interesting and zako-related scenes are here:
41:45 - 44:30 - main hero makes sex with one of them
49:00 - the prostitute with a gun appears (without a gun for now)
50:48 - 51:46 - a honey trap (there is another parallel scene during this time, but wait a minute)
53:15 - main hero is interrogated
53:33 - interrogation gets better
54:18 - and better
54:42 - 54:55 - the most funny moment
1:05:00 - 1:09:40 - main hero fucked the dead body of the prostitute before he realized she's dead
1:13:25 - a long scene starts
1:18:08 - henchwoman, who killed them, talking about dead prostitutes without any respect.
1:21:20 - 1:21:35 - henchwoman is dead