It took me hours to write this comment because I'm super excited by all the possibilities (babywol). But I tried to pare it down...lol.

Overall, I think you know your friend best so I say lead with what you know they like. What do they like about BTS - what do they pick up on first when a new MV is released? Or, if they have other group/ artist favorites, what are the common themes, e.g. musicality, vocals, dance, visuals, harmony, personality, etc.? Start with MVs / performances that highlight what they most like in a group and then, throw in a few things that are different from that initial theme but showcase the versatility of Shinee. E.g. if they are drawn to dance elements, start with Don't Call Me, Excuse Me Miss, etc. and then add a ballad.

Alternatively, if you want specific suggestions... Recently, I watched a bunch of videos on the YouTube channel Seoul Connection . The channel owner, Yetti, is Army and a friend mentioned to her offhand that Shinee are legends. She was not convinced and then fell hard. Here are a few of the videos that she watched, e.g.: -Don't Call Me (MV, stage, relay) -Dear Name cover live on IU's Palette -Replay MV -Y Si Fuera Ella live performance - Jonghyun - Ode to You live performance -A Very Shinee Guide (fan-made)