Here is the full list of all 18 OTXO achievements.
Kill 50 enemies with kunai
Collect all guns
Collect everything from the gachapon machines
Destroy the Heart
Vault over 50 times
Go fishing
Play fetch
Kill 50 enemies with grenades
Unlock all drinks
Kill 15 enemies with doors without dying
Clear a room by only kicking
Clear a room without using Focus
Kill an enemy with a thrown magazine
Order the ANIMAL drink at the bar
Roll over 100 times
Die for the first time
Clear a run on Impossible Mode
Clear a full run without taking any drinks