Debug menu:
To access the “Debug” menu, dive into the Cosmosphere, then hold L2 and press Triangle. You can use the options to set flag events, change character levels, character parameters, add money, and create completed saved game files.

Completion bonus:
Beat the game to unlock the “Extras” menu and New Game mode.

Trophies:

Bronze trophies
Bad Ending – Fail to defeat MYU before Song Completes.
Battle Enthusiast – Fight and win 100 battles.
Battle Lover – Fight and win 200 battles.
Battle Maniac – Fight and win 300 battles.
Chained Finnel – Finnel Cosmosphere L5 Event.
Coward – Run from battle 100 times.
Destroyer – Empty the Encounter Bar 25 times.
Finnel Friendship – 30% of Finnel’s Cosmosphere Completed.
Finnel Love Love – 60% of Finnel’s Cosmosphere Completed.
Finnel Love Love 1 – Phase 2 Finnel route Event.
Finnel Love Love 2 – Phase 3 Finnel route Event. Must have MAXED Hearts!.
Finnel Normal End – View Finnel’s Normal Ending.
Finnel’s Master – 100% of Finnel’s Cosmosphere Completed.
Frightened – Tilia Binary Field Game L3 Event.
Frustration – Collect Max DP for any one of the girls.
Game to a certain extent – Clock over 100 hours of game time.
Hot Springs Panic! – Phase 2 Event.
Longing for – Tilia Binary Field Game L2 and L3 Event.
Older Sister Sakiya – Saki Cosmosphere L9 Event.
On Stage! – Saki Cosmosphere L4 Event.
Phase 1 Clear – Complete Phase 1 of the story.
Phase 2 Clear – Complete Phase 2 of the story.
Pregnant!? – Saki Cosmosphere L8 Event, Auto if Saki is chosen girl (3 hearts) or accept her love.
Reunion with the children – Phase 2 Event.
Saki Friendship – 30% of Saki’s Cosmosphere Completed.
Saki Love Love – 60% of Saki’s Cosmosphere Completed.
Saki Love Love 1 – Phase 2 Saki route Event.
Saki Love Love 2 – Phase 3 Saki route Event. Must have MAXED Hearts!.
Saki Normal End – View Saki’s Normal Ending.
Saki Strips! – Saki Cosmosphere L3 or L4 Event.
Saki’s Groom – 100% of Saki’s Cosmosphere Completed.
Salapator’s Wedding – Phase 1 Event.
Saving often is necessary don’t you think? – Save the game 100 times.
Singing to create a new world – Finnel Cosmosphere L9 Event.
Soma Uninstall – Phase 2 Event.
Soma VS Soma – Finnel Cosmosphere L7 Event.
Synthesis Beginner – Synthesize 10 unique items.
Synthesis Expert – Synthesize 60 unique items.
Synthesis Intermediate – Synthesize 30 unique items.
The Long Missing Heart – Saki Cosmosphere L6 Event.
Tilia Friendship – 30% of Tilia’s Binary Field Game Completed.
Tilia Normal End – View Tilia’s Normal Ending.
Tilia’s Husband – 100% of Tilia’s Binary Field Game Completed.
Tillia Love Love 1 – Tilia Phase 3 Event