A bunch of boys serve as toilets for the school to help the students concentrate more on studying. The only problem is, all the boys want to take it in the ass, and nobody wants to be on top. How can they solve this issue? TL Note: Yui’s brother is named “Mai”. The kanji in his name can also be pronounced as “Bui”. Bui sounds like buhi, the sound pigs make when they oink in Japanese. It’s also how they pronounce the letter “V”.