My Dear Gangster Oppa – Kisskh English Subtitle

University nerd Guy secretly loves his best friend Wal. To relieve the loneliness of one-sided love, Guy’s hobby is playing games. It’s in a game that Guy meets a kind sister named Yuri who he later discovers is a handsome young mafiaso named Thiu. While Guy starts to open his heart due to Thiu’s gentleness, he gets to know Thiu’s mysterious and terrifying past.

(Source: iQIYI)

~~ Adapted from the webtoon "The Ideal Relationship" (호형호제) written by Ken (켄) and illustrated by Nod.