In the Omori game you can obtain a number of keys. These keyboard keys are labeled with a capital letter. The letter keys start with A all the way to Z. You can find the R key here.
Omori Location Key S
You can find the Omori S Key in an enormous clam at the end of the Underwater Highway.
Looking for Key T. Find the Omori Key T.
You can find all Omori key locations here.
This overview is intended to help you in obtaining every possible achievement in Omori game.