There are two scenes here. In the first one, the evil twin knocks out the good twin and steals her clothes. After the good twin recovers, she is taken hostage by the evil twin. The girl is knocked out with a knife butt to the neck.
This is a pretty neat sequence. Both the good and evil twin get knocked out (with belly punches). They are carried unconscious. There are also some extra art pages showing the unconscious girls.
From a Chie Shinohara one-shot. The main character is knocked out and thrown into a house, which is subsequently set on fire. She faints from the smoke, but is saved.
There is a very brief chloro. The girl initially thinks a certain thief (that she is in love with) gets killed, but he sneaked up behind her and chloroforms her. She is taken to his lair, where they make love or whatever.
The main female character is chloroformed for some sort of ritual. She's chained inside a cage and there are freaking panthers.
Author: Chie Shinohara.
A boy and a girl open a cupboard only to find sleeping gas spraying out. They are overcome and fall unconscious.
We find out the villain to be...Miss Sonehara, the evil evil evil antagonist of the series. Knowing her, the cupboard was probably filled with chloroform.
Author: Chie Shinohara.