ULPT - request, how do I ruin canned larger?

Posted by worldworn@reddit | UnethicalLifeProTips | View on Reddit | 250 comments

My brother in law drank all my nice cider while my sister was house sitting. (He wasn't even supposed to be there). After some considerable complaining he finally bought some cheap larger, that he likes as some sort of piss poor apology. Now we are having a bbq and he's coming round. Apparently he made some snarky comment about having something "decent to drink" clearly still bitter about being made to buy the replacement drink. So I doubly pissed off. Can I ruin the beer without it being obvious? He can drink as much as he likes then.