There is no Epic Loot here, Only Puns from royalroad is the only similar one I can think of, as it has a girl reborn as a dungeon with later her menu and system becoming sapient and even having humaniod forms though menu is the guy, and there hasnt been much said on romance for the time being.
The Experimental Log of the Crazy Lich - The MC is male though. The system is one of the girls being shipped with the MC. Spoiler: Details The system is actually the soul of a goddess and she fell in love with the MC after years of spending time with him