Stellar Transformations - Book 6 Chapter 14

Suzuki, an adult programmer, suddenly notices that he’s been thrown into a different world while wearing a casual clothes at level 1. He gained high levels and treasures after using the 3 times use-disposable-magic, Meteor Shower, at once. After that he intends to do different world “sightseeing tours”?

He meets 3 beast girls, beautiful purple and black haired sisters, and an eccentric blonde haired elf girl along with various people during his trip. Although there are occasional fighting with demons and demon lords, this is a heartwarming fantasy story at heart.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----

Ronan was just another overworked office drone until a sudden death transported him to a vast, unfamiliar fantasy world—alone, invincible, and armed with absurdly powerful abilities from a game he once played. But reality isn't as simple as a game, and after days of wandering the unending Nim Forest without finding civilization, his optimism begins to fade.Just as isolation threatens to wear him down, he encounters Frieren, a quiet elf girl hiding in the bushes. Their meeting marks the first step on a path neither of them fully understands, in a world that seems empty, yet full of mystery.

[The Demon King is Dead], a story in which the Demon King got immediately killed in the Prologue. I became the ‘Demon Prince’ of said novel.

…Help me.