Bokura no Sex

There's not many similarities between the two, but if you look at the cover of the first episode of both of these OVAs, you'll see that both feature a tomboyish girl with short hair and tanlines, if you know about the excellency that that emanates you'll agree that the recommendation of both is justified. Have in consideration though, Bokura No Sex is made by Queen Bee and you know what that means. 

Both are hentai featuring at least one girl in each with exquisite tanlines, one is tomboy, the other one is gyuaru, but whatever, Bokura no sex adapts three short stories from the manga of the same name, so only the first one with the short haired beauty is similar, but who cares? Those tanlines are to kill for, there's also a summer theme in both, maybe? Go for the tan, man. 

If you see the cover of Bokura No Sex you'll notice the beautiful tan lines surrounding the main girl and that's exactly the reason of this recommendation, Resort Boin is known for many reasons, between them is the fact that features one of the few tomboys with tanlines in hentai, at least animated, and that's exactly what Bokura No Sex also has, it's just in the first episode, the others are from masochism to shota on loli, since the rest animates other chapters from the manga that it's adapting, but that's enough for me.