Special attack sounds good in my opinion.
Though first we need some actual reason to kill these enemies.
The place after leaving tentacle room, where syahata is attacked by swarm of enemies while waiting for platform. It was pointless to fight there which would only lose HP, much easier was to let them rape syahata until the platform arrived and then just run away.
So the only place where we are actually forced yo kill enemy is boss.
And normal enemies lacks some sort of drops or anythin that syahata profit after killing