Here is the full list of all 39 Paradise Killer achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Achieve max hangout level with Doom Jazz
Achieve max hangout level with Akiko
Achieve max hangout level with Henry
Unlock all footbath upgrades
Achieve max hangout level with Witness
Achieve max hangout level with Yuri
Achieve max hangout level with Carmelina
Find all music tracks
Collected all bottles of whisky
Achieve max hangout level with One Last Kiss
Access the barracks
Complete the Syndicate HQ puzzle
Achieve max hangout level with Sam
Achieve max hangout level with Lydia
Collect all Island Sequence Mementos
Find all recordings
Collect all drinks
Acquire Elusive Chocolate
Speak to a [REDACTED]
Use the [REDACTED] to open the [REDACTED]
Achieve max hangout level with Crimson
Unload the cargo
Acquire the Pyramid Starlight upgrade
Tell the ghost who they are
Complete the valve puzzle
Acquire the Worship Starlight upgrade
Activate all Crying Grudge statues
Tell the ghost what happened to their friend
Deliver the manifesto letter
Give a treat to [REDACTED]
Access the Syndicate Graveyard
Deliver reassurance that justice was done (it wasn’t)
Return the missing gem
Acquire the Cosmos Starlight upgrade
Visit [REDACTED]
Collect every shrine tablet
Speak to every Shinji
Speedrun the game and complete it in under 10 minutes
Collect all Starlight Skins