This poem is called a cinquain. It follows this pattern:
Line 1: Noun
Line 2: Description of Noun
Line 3: Action
Line 4: Feeling or Effect
Line 5: Synonym of the initial noun.
So, here goes my poem about dementors:
Dementors
Dark, menacing figures
Roam around, draining happiness
Coldness and hopelessness floods them
Guards of Azkaban
It’s kind of odd, I think, but I did it just for the fun of it
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You know, just to try something interesting and new. Just to warn you, I may be experimenting with more types of poetry.