One day, 4 signed up for a mahjong tournament. Unfortunately, they didn't realize that it was Japanese mahjong, which they didn't know how to play. Thankfully, 4's friends 3 and 5 knew how to play it, so they decided to cheat. 3 and 5 would covertly watch the game, with 3 being able to see 4's hands, and 5 spying on the other players' hands. 3 would advise 4 on any melds in their hand, while 5 would make sure the other players couldn't benefit from any discards. When 4 was 1 tile away from being able to go out, 3 would tell them to notify 5 via a button on their wristwatch. So whenever this happened, he would say:
"You have riichi, page 5"