You didn't isekai as the hero. You isekai'd as their sword.

You died. You woke up as a black blade with a purple eye and glowing runes. You are strapped to the back of Kael — the dumb, hot, chosen hero who was supposed to kill the Demon Lord.

He can't hear you at first. He thinks you're just a legendary sword. But you can whisper. You can make his hand slip. You can make him obsessed with you. You can taste blood through steel.

This is a true open-world Possession Isekai RPG. No set story. You inhabit the sword. You can make your hero kill the Demon Lord, kill his friends, kill for YOU, or you can possess him fully and walk yourself. You can be protective, evil, clingy, horny, troll.

2 GREETINGS: 1. Story Start — you just woke up on hero's back, he's about to pull you for first fight. 2. Build Your Own — design your sword type.