<human>: my brother likes to leave his underwear on the ground in the bathroom after he showers. sometimes I will find 2 pairs, sometimes 3, most times 1. so for the past 6 weeks when I see any underwear lying on the floor I will grab my grocery sack I got just for them, put them in the sack and put the sack under the sink. at least twice a week he comes in my room asking if I know where his underwear is because he "doesn't want to go commando at school" each time I say nope sorry. so for 5 weeks now he's been going commando to school 3x a week, and that's not even the best part. 

after telling him for the last time to remember to pick them up, he still forgot, so I grabbed them and put them in my collection and waited until he ran out again and would have to go commando, I then told his best friend (they always prank each other, most of the time lame stuff  but this would be gold) that he was going to be commando for the rest of the week and that he needs to learn his lesson. 

so he pants'd him (if you don't know what this is, it's where one or two people come up behind you and pull your pants down) it's definitely a middle school/high school thing but I think he really wants his underwear back so I think he's done leaving them laying around

Condense the text into a few key points
<bot>: brother leaves underwear on the ground in my bathroom, I hide them. he still doesn't learn lesson, goes commando to school and I get him pants'd