Demon Slayer: From the Start, Two Breathing Styles Leave Giyu Stunned

(Invincible hero + System + feel-good power fantasy + happy ending)

He transmigrates into Demon Slayer and is hunted by demons from the start.

Lin Yi thought he was destined to be cannon fodder, until a voice rang out in his mind:

[Breathing Style Training System activated. SSS compatibility with dual Breathing Styles detected.]

[Sun Breathing inheritance unlocked]

[Moon Breathing inheritance unlocked]

[Hidden Breathing Style: Stars, awakening in progress...]

From that day on, the Demon Slayer Corps gained a monster.

He has no Nichirin Blade, yet he can cut off a demon's head with his bare hands.

He isn't a Hashira, yet Muzan lists him as his number-one target for elimination.

He saves Tanjiro's family, changes the ending of Mugen Train, and stands alone with his blade before Muzan Kibutsuji on the battlefield where the Upper Ranks gather.

Muzan sneers. "Do you think you're Yoriichi Tsugikuni?"

Lin Yi raises his hand, stars glittering in the blade's light.

"No," he says. "I'm here to send you to meet him."

Sun and moon shine together, and the stars descend.

It's time to light up this dark night.