If you want to buy a geoduck you have to go to the bank beforehand to deposit enough money. If you don't deposit your money you won't have enough in your account to buy even one! They're expensive, after all.
You go to the bank to make the deposit and there is a kid standing in your way playing with a yo-yo (よ). You try to squeeze past and he hits you in the face with the yo-yo! Now you can't see! Now you can't make the deposit!
Currently there are no similar looking kanji which exist in the WaniKani learning system