This one might be simple. 1.Erotic Coupling in general. The section is over stuffed with stories that could go into other categories. It may as well say Erotica. Most people see it and think hey my story is erotic. Coupling can get ignored with people adding group sex and other stuff not to mention it could be referring to bisexual, gay, or lesbian, mature, or teen couples. Not sure what to call it. Romantica- Romance erotica. Maybe might help give the section a little breathing room if its farther back in the mix but I am not in love with the name Romantica.
2. Teen --> Adolescence. There are 131 stories with the tag teen but only 30 of them are in teen. This category gets over looked by people actually writing teen stories who might get more love for there stories if Teen wasn't the third to last category on the list. I think renaming it adolescence might give it more attention as well as grow the section which has a 98% like rate.