These verses are parodies of the song "Hakuna Matata", from Disney's animated film The Lion King. I wrote the first two stanzas on 2018-01-14, and the other two on the publication date above.
Consider this a companion piece to "Huge Katana".
Hakuna katana: what an elegant blade Hakuna katana: only Nippon-made It means bushido, for the rest of your days Bisect knights with ease Speak Japanese Hakuna katana Hakuna katana: cut down knights from your horse Hakuna katana: follow honor's course It means no mercy, and it means no remorse Your whole life will be Blade mastery Hakuna katana Hakuna katana: train in samurai schools Hakuna katana: kill impudent fools It isn't murder if you follow the rules With a single slash Turn foes to hash Hakuna katana Hakuna katana: fill opponents with dread Hakuna katana: slice off someone's head You'll practice living like you're already dead One day you may be Like Musashi Hakuna katana