It's not okay to trap or set up another person.
Brian is staying at Kai's house when Kai sleepwalks into a bathroom.
Brian wants to experiment with Kai's sleepwalking.
Brian talks to Kai through the bathroom door, trying to get him to answer questions.
Brian holds the door shut so Kai can't get out easily.
Kai gives some nonsense answers, leaves the bathroom, and goes back to bed.
Kai stands in the bathroom sleeping for a long time and wakes up tired the next day.