In Evanescent Existence, there are two playable characters to choose from in v1.01a, and a third playable in v1.10a.
For the main scenario, you actually play as Tsurubami, not Tsubakura, because Tsurubami is disguising themself as Tsubakura. Thus, the alternative Stage 3 boss is occupied by Tsurubami. To unlock them, complete the Extra stage with Yabusame. You play as the real Tsubakura in the Extra Stage.
The real Tsubakura in the Extra stage.
Crafty and Treacherous Memory Passing Through
Suzumi can be unlocked if beating the game with Tsubakura.
|| Weak-Willed Youngest Child
Cool-Headed Hot-Heeled Thermal Runaway
Ambiguously Paper-thin Archaeologist
Eternal Senselessness with a "Chaotic" Alias who Manipulates Gravity at Will
Wilhelm von Clausewitz Halcyon HISUIMARU
See #Playable Characters for information about playability.