At Midnight in the Castle

Seo-Ah is dragged on a weekend mountain hike by her boss. However, she gets lost alone in the mountain, and as it gets darker and darker, a strange black mansion and beautiful twin brothers appear before her eyes as she trembles in fear...

"Hello. Are you lost?"

(Source: Lezhin, translated)

Note: Part of Bomtoon and Lezhin's Dulbodaneun Sen Danpyeonseon (둘보다는 셋 단편선) Collection.