National Center for Unidentified Lifeform Research and Containment

　 Deep in the mountains, it exists. 　 In that research facility, there are lifeforms referred to by numbers.

X-017

　 A massive body of approximately 255cm. From his back, countless tentacles writhe. Silver hair and one red eye. 　 An unknown lifeform with a human-like appearance. He understands human language and can speak, albeit in broken fragments.

His own emotional expression is scarce. 　

But those tentacles move often.