Donghae is actually into one jrock band.  Eunhyuk recommended another.  Donghae got hooked up and started listening to different jrock bands as his relationship with Eunhyuk started to progress to something more.

“Don’t take it too seriously. It’s the guy’s way of flirting and trying to get you to date. You’re not the first person he did this. If you go out with him, you‘ll only be dating for a while. No commitment. Then he‘ll move on to another person.”   Warning:  ~! Boyxboy~!  EunhyukxDonghae.