As a 20+ adult, I really enjoy titles with lots of angst and BDSM elements. View Finder is a perfect mix of angst, kink and story line. I really love the push and pull dynamic between Asami and Takaba. The art is gorgeous, although the concept and writing could use some work.
One thing that worries me about recommending this series to others is that Viewfinder very much glorifies rape and calls it consensual (or, in fandom world dubcon). So keep that in mind if you're going to recommend this to others. The trigger warnings that should be applied are various and serious.
EDIT: this is for the manga. Sorry if I missed up, I'm just getting to know the site again.