If you go to the “Metaverse” fake desktop (by exiting DDLC in-game, NOT exiting to your xbox dashboard), you can open a folder marked “files”, then a folder marked “game”, then a file marked “poemwords.txt”. This will give you a list of Sayori's, Natsuki's and Yuri's favourite words to use in poems. Exclusively use words from the appropriate list to write a “perfect” poem.

Yuri (alphabetically):
9:15 (this is actually a clue for a puzzle),
afterimage, agonizing, ambient, analysis, anxiety, atone, aura,
breathe,
cage, captive, climax, contamination, covet, crimson,
desire, despise, destiny, determination, disarray, disaster, disoriented, disown, dream,
effulgent, electricity, entropy, essence, eternity, existence, explode, extreme,
fester, fickle, flee, frightening,
graveyard,
heavensent, horror,
imagination, incapable, incongruent, infallible, inferno, infinite, insight, intellectual,
journey, judgment,
landscape, lust,
massacre, meager, melancholy,
philosophy, pleasure, portrait,
question,
raindrops,
secretive, sensation, starscape, suicide,
tenacious, time,
uncanny, uncontrollable, unending, universe, unrestrained, unstable,
variance, vertigo, vibrant, vitality, vivacious, vivid,
whirlwind, wrath

Here is a more detailed guide that I did not make:
https://gamefaqs.gamespot.com/pc/222637-doki-doki-literature...

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