Light reclines casually on his bed. He appears to think this is how a person would naturally behave around the detective investigating them.
"You seem remarkably unconcerned, Light-kun," you inform him.
Light sits up at once, looking nettled. "Of course I'm unconcerned. I know I'm innocent."
"Is that so?" you ask. "Then you won't mind leaving me to look around by myself."
Light clearly hates the idea. But it's equally clear that he can't object without appearing suspicious. He reluctantly leaves the room.
If you take a look around, maybe you can get a general idea of Light's character.
You look through Light's bookshelves. All of the website creator's Death Note fanfiction appears to be here, covered in furious 'I WOULD NOT DO THAT' scribbles.
Hidden in a sleeve, you find a number of pornographic magazines, which you suppose might tell you something about Light's masturbatory habits, if that's the sort of thing you were hoping to find on this website.
Or perhaps it would be better to go back downstairs.