Holy_mackrel

Love Triangle development later...but not whom you expect. So an advance warning. 
______
The world's No. 1 Beloved Hunter has a secret. She's a female and second, she's a lazy know-it-all who does not want to do anything but laze around and have fun. 

The dungeons? Not her concern. The tower that marks the progress of humanity? That does not feel as important as her college entrance exam result she is failing. The only concern Nero has is to keep her identity a secret from her sick mother and to make sure she lives a calm life. 

But that’s easier said than done when one is the older sister of an S-ranked hunter as well as a genius potion maker.

Nero wants to live a calm life, but the world does not want her to live while hiding. And the biggest culprit behind her life being turned upside down is no other than her own patron - the mysterious being called ‘?’ who keeps on wanting her to fully apply her potential and to maintain her crown as the world’s #1.
______
There will be romance.

The World's #1 Beloved Hunter has a secret

Hwan raised his hands quickly, stepping slightly in front of Nina. "Everything's fine!" he said, his voice light but edged with tension.

"We're just leaving now. My partner and I got a little turned around, that's all."

The guard gave them both a long, suspicious look. His eyes swept over their clothing—Nina's casual modern wear and Hwan's sleek hunter gear.

He muttered something under his breath—something that sounded a lot like "foreigners" and "weird fashion choices"—before turning away and heading back to his post.

Only once he was out of earshot did Hwan exhale. He ran a hand through his hair.

Nina stayed quiet, watching him carefully.

"I'm sorry. I really don't know what's going on inside this dungeon. But I'll contact someone from the outside. Maybe they've seen something like this before."

Ch 89: The Dungeon of the Past- Part 2