Pleasant
The soul of a person has a hook that can make them pleasant. When you see, hear, or feel something pleasant, can't you feel that hook pressing into the middle of your body?
Imagine that feeling you get when everything is just SO pleasant. There is a pressure from your soul's hook digging in. It's a good feeling though, a pleasant one! It isn't too hard or too soft.
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If you want to feel this pleasant feeling just look at a kayak (かい). Kayaks are the most pleasant boats in the world. Feel that pleasant feeling in your chest just from reading about kayaks in this mnemonic right now.
Go look up pictures of kayaks to get some of that pleasant high. Mm, your soul is hooking you real good.