Castlevania of the Pigeons from Fairy Tail

Finally, after going through many hardships and dangers, covered in blood, the challenger reaches the top floor, where he will encounter the demon king Endymion in front of the sealed door.
He will be shocked and despaired to find that this is the "good partner" who has sold him various goods along the way, and it is this "good partner" who smiled and ended his life with his own hands, allowing him to be reborn at the entrance again and start all over again.
Gradually, word spread among those who challenged Castlevania: Never trust anyone you meet on the road, no matter if they are good to you or bad, because they may very well be the final boss, a bastard who wants to squeeze all your value out of you...
The top floor
Heart: Endymion
Third Floor
Leader: Maldor
Elite: Crazy/Sera/Trafusa/Storm/Esel/Keith/Jackal/Silver/Franmars
Normal: Rami/Dark Mage of Hades' Gate
bonfire:
Second Floor
Leader: Precito/Brunoto
Elite: Urutia/Azuma/Lastyros/Zancro/Melty/Huayuan/Zudiel
Normal: Yumaz/Kawaz/Demon Heart Dark Mage
bonfire:
First floor
leader:
Elite:
usually:
bonfire:
Cemetery
References: Anime/Rabbit Elements/Slay the Spire/Fairy Tail

Novel Keywords: From Fairy Tail: A Rogue Demon City (no pop-up ads), From Fairy Tail: A Rogue Demon City (full text download), From Fairy Tail: A Rogue Demon City (latest chapter reading)