He does it by making mom clean upstairs.

"Alright let's see your homework", Natalie said somewhat annoyed, "Well, i don't remember if i had to learn this this early, but whatever, let's do it", she said looking at the math books of everyone.

"Wow, your big sister is very smart Luke", commented Emily looking at the speed that Natalie was resolving their homework.

"At this rate, she'll finish the homework within a few minutes, i must do something to extend her stay down here", thought Luke for himself, wanting to extend Natalie's humilliation.

"Excuse, i must go to the bathroom", Luke excused himself before leaving the common room searching for his mother.

"Hey mom, can i ask you something ?", he said to her.

"Yes sweety, what do you want ?", his mom ask.

"Did you cleaned out the the upstairs rooms ?", he said.

"No, i haven't , but why do want to know it ?", she replied.

"Well i was thinking about giving my friends a tour of the house, but surely they wouldn't like seeing a uncleaned mess up there, won't they ?", he responded.

"Oh well..., in that case i'll give the upstairs an extensive cleaning session right now", she declared.

"Good, that'll keep her out of her room for a while", Luke said to himself.

Meanwhile back at the commom room

"It took a little while, but at last that's all of your homework", Natalie said happily.

"Can you stay here a little more still", said the lusty David.

"No!, i'm going to my room back now!", she declared before going towards the stairs.

"Sorry Natalie, but i'm cleaning upstairs now, so you can't go back up for now", Her mother said.

"Why not?", Natalie demanded.

"Becuase you could slip on the floor and injure yourself while the floor is still wet, so wait for an hour before it's dry, either way be nice to our guests today", she explained to Natalie, before she went back upstairs to clean some more.

"Looks like you'll have to stay here a little more", teased Luke.

"Whatever..., just...whatever, what do you want ?", said Natalie annoyed.

"Well, i was thinking that we could play something", said Josh.

"And what do you want to play then", she asked them with an tired tone.

Ashley was the first one to speak, and she said, "How about...."