It was only then that he noticed the peg was already occupied by a coat he didn't recognise. He had a big family, sure, but he knew his mum's coat by sight, his sisters had moved out a long time ago and his dad still wore a blazer (which gives you an idea of what an up-to-date and advanced person he was). Nobody else could be home, except his older brother, who either didn't need or didn't want a coat. He owned a SNES and Primal Rage, which made him cool, or something.
This, of course, isn't the sort of thing I'd notice, mostly because my sister appeared to own a different coat every week. Even so, I doubt I'd have been curious enough to go up three flights of stairs and walk straight into my older brother's room, without knocking, to ask whose coat was on his peg. Except this is Lightsinthesky we're talking about, so of course, this is exactly what he did.
In the split-second between opening said door and noticing his brother, naked, spread-eagled on top of a young lady and "goin' at it on the bed" (as Lightsinthesky so poetically phrased it when recounting his escapade to us in the cafeteria the next day), he remembered whose coat it was. Said person wasn't wearing the coat any more. She wasn't wearing anything else, either.
So what do you do when you walk in on your older sibling having sex, specifically with someone you don't know they're having sex with?
"Hey," said Lightsinthesky, "so I'm just going to town. Might get a bite to eat and do some shoppin', but I'll be back before dinner tonight. Say hi to Mum when she gets back and tell her I'll bring something from Tesco."
And he walked out.