Responses
Drugs were brought by seongrok from Je-oh's place so police couldn't find them if they searched his place after he killed that blonde dude.
And camera is the same when he filmed a porn for seongrok to watch to display his abilities and said that he wanted him to fuck him on camera like this. It's not random.
Who just goes "let's get high and bang" and who just has drugs and recording equipment laying around.