No 4s allowed
In Japan, they avoid the number four because it sounds exactly the same as 死 (shi), which means “death.” This is similar to how we in the West avoid using the number 13 for floors and rooms as it’s considered highly unlucky.
But the superstition that four is an unlucky number doesn’t just extend to missing building floors. Some buildings have even removed floors 40, 42, and 49 are completely gone. If you’re going to give somebody something, avoid giving them items in fours. Also, don’t give somebody a watch, not even a Rolex (so ignore the Valentine’s Day gift suggestion) since it symbolizes how much longer someone has to live. Pretty ominous, right?