Demon Slayer: From the Start, the Butterfly Family Took Me In

Female leads: the Kocho Sisters, and no one else. No romantic ambiguity.

There are two female leads. If you don't like that, please steer clear. Don't flame me.

The male lead isn't a local, and he's exceptionally talented.

A modern man transmigrates into Demon Slayer after dying in an accident. Abandoned, he is later taken in by the Kocho family and finally receives a name filled with his family's love, just as he had always wished. But that happiness is shattered by demons... Watch as the innocent Kocho Tenma finely chops Muzan into mincemeat.

“I really have been afraid all along: afraid that you might die in front of me, and afraid that I might die in front of you. But when I think about it, as long as we're together, there's nothing to fear.”

“Oh my! Tenma isn't innocent at all, is he? But that's all right. No matter what, Tenma is always as adorable as ever!”

“Big Sis! You're spoiling him way too much. And Tenma, did you eat my ginger simmered in soy sauce again?”

“Oh my! Shinobu, you mustn't eat people. That's something only demons do!”

“I don't care! I'm going to bite this jerk to death!”

This sort of farce plays out at the Butterfly Mansion every day. Tenma, the person at the center of it all, looks down at little Shinobu sprawled in his arms, using his arm as a teething toy, and smiles happily.

“Another peaceful day, then!”

Tanjiro, a regular at the Butterfly Mansion, watches the three of them inseparable beneath the covered walkway. He says nothing, but the corner of his mouth lifts into a faint smile.

After it is all over, the Hashira exchange glances and smile at the three butterflies still play-fighting together.

“As expected of Tenma, full of energy as always!”

Every Hashira survives. No angst from beginning to end.