Hikari appears bound and gagged on a railroad track, and her grandfather comes to rescue her (there is some time traveling thing going on.)
Turns out it's a trap and the kid gets injected.
In this scene, "Sargon, Mistress of War" is possessed and attacks her ally, Lord Cumulus. Another character, Lord Chaos, intervenes, KOing her with a blow to the back of her head!
Toshio is gassed again, this time by a female detective in glasses. She holds a cloth over her own mouth to protect herself from the sleeping gas.
Later in the volume, a bunch of party goers are gassed by Hitomi. The trick is on her though, as everyone managed to sneak gas masks on.
All three girls get gassed by a woman weilding a spray can. They wake up bound and gagged. Nice scene!
Side note: This manga has a lot of bondage in it, but most of it is not appropriate for this site.